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Help! Hard-drive space doing the disappearing and reappearing act!

by Lee Koo (ADMIN) CNET staff/forum admin / October 2, 2009 2:35 AM PDT

Help! Hard-drive space doing the disappearing and reappearing act!

I enjoy reading and learning from your column. I have learned
a lot of helpful things from your members, but I am still
definitely a newbie. My question is about my hard drive. I
have a two-year-old Dell with Intel Core 2 Duo running
Windows Vista, 32-bit. Hard drive C is 300GB. A few weeks ago
it showed that I had 3.8GB left and the line was way in the
red. I did all the usual things like disk clean up, defrag,
clearing the cache, and I uninstalled a few things that I
don't use. I managed to get it up to 34GB available. I should
tell you that there is no way that I have that much stuff on
my computer. Just to be sure I bought a 1TB external hard
drive to transfer some of my pictures to. Before it arrived,
one day I checked to see what was left on my C drive and wow
it was back down where it should be at about 180 used. Today
the same thing happened. I'm back at having only 7.7GB free.
What the heck is going on? I have hardly added anything to
the computer since the last incident. Everything that I
download now goes directly to the external HDD. I have no
idea how it fixed itself the first time or why it has
happened again. I need helpppp!

--Submitted Lorilou L.

Here are some featured member answers to get you started, but please read all the advice and suggestions that our
members have contributed to this question.

Windows Swap File and program caches --Submitted by darrenforster99

Hard drive space variation --Submitted by Zouch

Where is your space going? --Submitted by Watzman

Could easily be System Restore, Lorilou --Submitted by warpete

Re: hard drive space --submitted by Kees Bakker

If you have an solution for Lorilou, please click on the 'Reply' link and submit your answer. Please be as detailed as possible when providing a solution for her.
Thank you!
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by eeyore08 / October 9, 2009 4:48 PM PDT
In reply to: Hard Drive Space

No Norton here. I use Trend Micro and I don't have any problems with it. (That I am aware of)

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Mystery disk space

300Gb isn't enough disk for Vista. Not a lot left for your programs, temp files and virtual memory.

It sounds like you have one or two things to look at. The main culprit is likely the Virtual Memory, AKA Paging File. If you allow Windows to manage it, it is possible for disk space to go up and down. The virtual memory manager in Windows works pretty well until the disk gets pretty full. (That's when you can get the mysterious "out of memory" error). Try not allowing Windows to manage the virtual memory. You do this by setting the min and max pagefile size to the same. The next is your temp files. If you can, they should be on a separate physical disk. Many programs are bad about cleaning up their temp file useage when the program is exited, and this can also make the disk useage fluctuate.

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Re: Mystery disk space
by lorenbc / October 3, 2009 2:45 AM PDT
In reply to: Mystery disk space

I would suggest you download and run TreeDirStat (free), which will help you analyze exactly where your space is tied up. Many have already mentioned System Restore Points as the culprit, but, it isn't always. In my case, it turned out to be a single file called spooler.xml, which kept growing to fill any available space that I cleared. The fix wasn't just to delete it, but also to turn off (and then back on) the service that logs printing errors. I would never have found that file without TreeDirStat. Once I knew the file name, I simply Googled it and found the answer in one of the first links that came up.

Good luck; please keep us posted.


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Several possibilities

If the problem was only a few GB, it could be just the page file growing and shrinking as needed but the space change seems way beyond that explanation.
If you visit many sites that have lots of audio or graphics, especially video, you could be filling your space with temporary files. Again, if that was the case, emptying your internet cache should have removed most of those but it sounded like you tried that and not much was removed.
You can use CCleaner to clean junk files and to clean up your registry as well.
You could be infected by malware that is using your system to stage file transfers. If you're not running a real-time antimalware product, you should be. Even if you already run antimalware software, you could scan with a couple of others just in case. There are many free antimalware products but Spybot Search & Destroy and Malwarebytes Anti-Malware are two good ones. Note: If you are using other real-time antimalware, just use them to do full system scans and do not activate their real-time components because that could conflict with your existing product.
All the programs I mentioned are available through CNET Downloads.

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highly variable drive space
by zepper / October 2, 2009 2:43 PM PDT

Hi Lorilou,

Your problem is probably and mainly due to dynamic "virtual memory". "Virtual memory" is hard drive space that is used for shifting stuff (parts of and/or whole programs and data) from RAM when the RAM gets too full - dynamic means that the space it uses will vary in size based on what Win "thinks" it will need. One option is to add more RAM (I like a minimum of 2 GB), so that shifting won't be as necessary. Another is to switch to Static Virtual Memory, where you can set the min. and max. sizes for your swap space (there are articles around the web to help you in estimating how much space you might need). Some programs manage their own disc caching separately and the RecycleBin can also take up to 10% of a partition's space even if it all isn't being used at the time. RecycleBin size(s) can be adjusted from the Properties choice on its right-click menu. With the huge size of today's drives, the 10% default (at least on Win XP and earlier) is a waste of space. I usually set mine to 1% or less as I generally do a permanent delete (shift-Del) anyway, rather than sending stuff to the recycle bin.
. Then there are some malware beasties that stuff drives with junk, but those don't generally clear after a shutdown cycle.
. One useful tip is to shut down each of your running programs separately before shutting down Windows - that way they can take care of their own messes (.TMP files, etc.) before Win shuts down.

To help with freeing up more space, there are Freeware drive cleanup programs that can help remove junk that accumulates on your drive. This stuff generally remains over a shutdown cycle, so isn't likely a part of your disappearing/reappearing space problem. but it doesn't hurt to clean it out too.

One popular and recommended one is CCleaner (crap cleaner). I download most of my free utilities from But you need to understand what it removes before running it for the first time. In particular, I don't let CC remove my Cookies because it removes them ALL, not just the hinky ones (the spyware cleaning tools (MalwareBytes, Adaware, Spybot, etc.) do a better job with cookies - generally removing only the hinky ones).
This will remove "scratch" files (.TMP, .TEMP, etc.) that are left on the drive by instances of not having closed programs before closing Windows, etc.

Good luck,

Message was edited by: admin to add on additional information provided by zepper and deleting other additional post.

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hard drive loss

this is by no means THE diffentive answer, but if your using the standard windows deletion program, in my opinion you messing yourself over.for starters windows doesn't "delete " anything.....just tells the comupter to forget where it is stored. it stays there waiting to be overwritten.what you should be getting is a wiping program ( i use disc scrubber and bc wipe).both are DOD rated programs and get rid of all those extra junk files that take up space that you could put to better use

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Win XP OS -- Hard Drive clean up
by JohnSS / October 2, 2009 7:05 PM PDT

I found this formular in one of the Tech Help sites.

Disk clean up Extended:- Start ? Run -- Cut and paste this in run Box.

%SystemRoot%\System32\Cmd.exe /c Cleanmgr /sageset:35 & Cleanmgr /sagerun:35

Click OK
sure cleaned out plent rubbish -- No harm found

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Win XP OS - Hard Drive clean up
by eberwhw / November 8, 2009 6:47 AM PST

The code you suggest keying into RUN I believe is simply the Command line to run Disk Cleanup. This is surely probably, the first tool one uses regularly to clean the Drive of un-necessary temporary files, such as installation files and internet cache. Accessed easily by putting a shortcut on the desktop by right clicking on Disk Cleanup. START/All Programs/Accessories/System Tools/Disk Cleanup/Right Click/ Create Shortcut. In DC Boxes are ticked to select what you want to get rid of or compress. There are very good utilities available free, best one for me is "Advanced Systemcare", because with one click it does everything, but if you have time it will allow you to go through the fine detail to see what it's recommending. It's very fast in operation and does everything from cleaning the Registry, clean out junk files and privacy sweeping for invasive internet activity,spyware removal,Disk defrag, scans for Active X and Windows systems for hijacked settings and optimises your windows settings and internet settings, all at the same time I use the Advanced SystemCare Pro 3.3.4, which is paid for, but for over a year I used the free version. Both available from CNet. Another great cleaning tool also free, for people who have more advanced knowledge, is Easycleaner, you could just use this utility for disk cleaning junk and unnecessary files. It has a useful Hard drive analyser. Hope all this is useful to those who hate the Windows menu system and the changing withwith each new release. If they don't get it sorted with 7, I'm changing to Linux

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Tuneup Utilities 2009

The samething happened to me but I was able to fix that all I did was go to this web site which is and download and installed the software. You get a 30 day free trial to try it out. You get all the features to try it out. It has everything from Optimizer to Registry Cleaner it also fix windows problems too.

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Just a short note from me, The Winsxs folder
by MarkFlax Forum moderator / October 2, 2009 8:06 PM PDT
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your hard drive
by frankgw / October 2, 2009 10:21 PM PDT

open up computer by taking side off..locate your hard drive...disconnect the white power plug from hard will see a little set of pins ..usually one and 3 sets of two pins looking from left to right..if ther is a little plastic plug connecting 2 pins take it out...reconnect power plug to hard drive..restart computer..check hard drive size again...if you've still got the same onto disk any files you don't want to loseand reinstall your operating system

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Could easily be System Restore, Lorilou
by warpete / October 2, 2009 10:59 PM PDT

Lorilou, consider that a 300GB hard drive (manufacture's size) is seen by Windows as approx. 278GB's (different way of computing size). So, the difference between 278GB and your 180GB's of used space is: 98GB's. Windows uses "System Restore" in the event you need to restore your computer to a good working state. System Restore can easily take up 15% of your Hard Drive, and may use much more when you have several restore points all taking up space. Windows usually gets rid of the oldest restore point as it adds another, and normally when you add a new program or driver, Windows creates another restore point. Personally, I do full backups of my entire system, so I have System Restore turned off completely. If you have only one restore point taking up 15% of your HDD (278GB) then you have over 40GB's occupied by System Restore. What if you have three restore points? It sounds to me like when Windows reported you very low on space, it was due to System Restore. Windows then purged several restore points, and-------- reported more space! A marvel of Technology! This is what I suggest:
Open up a command prompt by typing CMD in the search box. When you type CMD you will see "CMD.exe" has been added to the top of the list under programs. Right-click "CMD.exe" and choose "run as administrator". This will open up the command window.
At the command prompt, type the following (copy & paste if you want):
vssadmin list shadowstorage
Press Enter
The above command will list the current amount of used, allocated and maximum allowed storage size for the Volume Shadow Storage (VSS) on your system.
To resize the amount of disk space that Vista allocates, type the following exactly as shown and then press enter when done (copy and paste is easiest):
vssadmin Resize ShadowStorage /For=C: /On=C: /MaxSize=2GB (You did state the "C" was your hard drive).
You can adjust the size if you like (2GB-4GB etc.), but I believe that 2GB's is more than enough. Now, System Restore can not build up to huge amounts on your hard drive and you are still protected should you need to do a restore. By the way (smile)----learn how to do a complete system backup. It's not difficult and can be a real life-saver. Then you can turn System Restore off completely. I hope this helps you!

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Yes, System Restore, but
by rje49 / October 9, 2009 10:12 AM PDT

Wouldn't it be easier for a novice to open the System Restore control and move the slider down until you get to 2GB's worth? BTW, you know how in XP the max was 12%? I never used Vista, but I see on W7rc, you can go all the way to 100%!!!!!! Let's see, on my XP, I'm at 1% with a 320GB HD, and I currently have 66 restore points.... so if my machine is ailing, how far back would I need to go? I mean, who's going to fight problems for that long before fixing it? I know, don't ask. Too bad I can't set it for 1/4 of 1%.

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Sys Restore Slider?
by celler dweller / October 10, 2009 4:43 PM PDT

Help I can't find it on Vista?

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Sys restore slider
by eeyore08 / October 10, 2009 5:16 PM PDT

I can't seem to find a slider to move in Vista.
Thanks though

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System Volume Information folder may be the culprit
by srinathn / October 2, 2009 11:28 PM PDT

Hi, Look into the contents of the System Volume Information folder and MSOCache folder of C drive. Though it may not be possible to look into them through windows explorer(In VISTA, it reports Access is denied.), try doing it with a Linux live CD.

I have deleted the contents of both the folders with no harm inflicted to the windows OS till date; and I delete both the folders all too often. However I am not quite sure whether any important files/data are in those folders.

Once I could recover 40GB from the System Volume Information folder and the system is still stable.

So give it a try! Its worth the space Happy

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Hard Drive Space.

It is possibly the Master Fat File. Have your cleaned your registry and then done DISK CHECK?

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Temp files and defualt installation

Even with saving all program installers to your external drive, the default installation option usually puts the actual program on your C drive. When it asks you where to install software, just change the letter of the drive at the beginning of the destination to the letter of the external, ex. <C:/Program Files/{name of company}...> becomes <D:/Program Files/{name of company}...> If the installer doesn't give that option, manually moving the folder to the external and then changing the target of the shortcut on the desktop, quick launch or start menu to the new location (usually just changing the drive letter) should work. For example, let's say there is a "Mozilla" folder containing Firefox program files. Move the entire folder into the "Program Files" folder on your external drive (if the folder does not exist, create it).

The other problem could be temp files. When you "open" a large program installer, it saves it to a Temp folder in the system folder which is in the drive that the OS is installed in (in this case, the C: drive). These files are deleted periodically, but you can also delete them yourself. First make sure you can view hidden files and folders,(On XP) go into control panel, folder options, view, and find "hidden files and folders. Then (again, on XP), go to your C drive, then "WINDOWS", then "Temp." Note that some of this data is important, so make sure you only delete files that you have directly downloaded.

Hope that helps, and good luck.

*P.S. Although this guide was based on XP, similar attempts should work in Vista.

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Hard Drive Space Disappearing
by GEO2003 / October 3, 2009 4:13 AM PDT

So far you have 2 steps to check based on others suggestions.
1- Run a program that will tell you what is using your HHD.
2- Run the VSSADMIN command in administrative mode to reduce your shadow copies.

I just want to add the following :

1- I Woul like you to re-set the swap file in case it is corrupted it by doing the following.

Click on the start Button, Select Control Panel, Select System and Maintanance, Select System.

Select Advance System Settings - On the new windows that opens :
-Select the Advance Tab
-Under Performance select Settings - then select Advance.

Now you are at the window that shows you the VIRTUAL MEMEMORY - This is the page file that Windows Creates to swap information back and forth from the Hard Drive.

-Select Change - at the top DE-SELECT - Automatically Manage page file size for all drives.

- MAKE SURE THE C DRIVE IS SELECTED - By the highlight in blue.
- Click on NO PAGING FILE - At the bottom of the windows

- THEN CLICK SET - this is important. The values on the top windows will change to Zero. Click Ok, until you close all the windows.
- Reboot your pc.
After rebooting your pc, the file will not be visible because it is consider a Windows Protected File.


- Click on Start, on the search box type - Windows Explorer - Launch it.

- Select Organize - On the drop down menu select - Folder and Search Options.
- Select View
- Select Show Hidden Files and Folders.
- DE-Select - Hide Extension for all file types.
- DE-Select - Hide Protected Operating System Files.
Click ok until you are back at the Windows Explorer Tree.

Go down until you see your C drive - Click it once, this should show you all the files on the Root Directory, if it does not, close Explorer and re-open it again and now click on the C drive.

You will see the Page File, Delete it and re-boot the pc.


- If you have 2GB of ram you can leave it off, Windows will use your RAM more ( which is faster ) instead of swapping to the HHD. But if you use a lot of applications at once. You might want to set it again by repeating the above steps and seting THE MIN AND MAX to the same amount which now makes it STATIC or Unable to grow. The MAX SIZE is listed by Windows at the bottom of the Window where you set it to Zero before.
So don't worry, you can always go back and set it if you ever get Out of Memory messages. But with 1 or 2GB i doubt this will happen.


This is more difficult but if you don't find the solution by the recommended steps of others here.

You may be seeing a problem with your Bios and the the way your Bios is seeing your hard drive.

Re-boot your pc and when the dell splach screen appears, press and hold F2, this will put you inside the BIOS.
Look for a Section that reads - RESET ALL DEFAULTS. Log off by saving your changes and let the PC continue to log on to Vista.

Or it could be that the internal Hard Drive Cable that connects the HHD to the motherboard could be LOOSE.

I don't know from your comment if it is a laptop or a Destop. If it is a Desktop.

Try reading the manual on how to open the PC cover, make sure you disconnect every cable to your PC including power.
Once you open the lid, GROUND YOURSELF, by touching the power supply for a few seconds.

Now look at where the hard drive is, and follow the ribbon cable to the motherboard.

If NON of our suggestions help you and If you purchase an additional Extended Waranty from Dell, you may still be cover by it and you can call them or you can log on to your account at the Dell site and initiate a HELP CHAT WITH THEM to see if they can give you additional support.

Hope everything works out.

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Crisp & Clear
by eeyore08 / October 10, 2009 5:39 PM PDT

Wow!!!!! Thanks for all. This was like having a tech sit beside me at my desktop and tell what to do & when to do it. Every thing you said worked exactly like you said so I was able to set up everything the way you recommended. Lots of people are using XP and things are not in the same spots. I did however stop before I had to take off the cover to check the cables. Scary stuff for someone with 10 thumbs. The treesize program helped a lot and I regained 180GB of space which after 24 hours I still have. After following your suggestion I am hoping that this is done.

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Re: hard drive space

There's a clear clue in your post "Everything that I
download now goes directly to the external HDD." It doesn't. It's downloaded to your TIF (Temporary Internet Files), then copied (not moved) to that external hard disk. Clear the TIF and it's gone. Don't clear the TIF and it's there. With the usual settings (use 10% of the hard disk for the TIF), that's 30 GB. If you think that's too much, change the settings.

The usual analysis of what you have is done like this:
1. Download TREESIZE from and run it to get a clear picture of the size of all your folders and subfolders. Note the total.
2. From the disc cleanup wizard, delete all but the latest system restore point. That should leave it at less than 1 GB.
3. Run chkdsk. That should tell you the exact size of all files together (and some overhead for file system and folders).

The amount of space used from TREESIZE should match the amount of space used by files from CHKDSK. The difference may be the 1 GB for the System Restore (the very hidden System Volume Information folder) that TREESIZE normally doesn't see.
There are some exceptions known when some there are some mysterious other files in that very hidden folder and the difference between CHKDSK and TREESIZE are much bigger that that at most 1 GB. But those are exceptions that can be handled.
But usually it all fits and matches and every GB can be accounted for. And if you include the System Volume Information folder by giving yourself access via the icacls command I'm sure every sector can be accounted for.

Prepare yourself of an evening of counting and calculating and you know everything you want to know.


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Hard Drive Space disappearing - Part 2IGH From Geo
by GEO2003 / October 3, 2009 4:36 AM PDT

I forget something very important.

Once you follow the recomendations for using applications to find what is using your HHD the most and once you delete the Page File.

Please run a check disk on your hard drive.

-Click on start.
-Select Computer - This shows all your drives.
-RIGHT CLICK ON C DRIVE - Select Properties on the drop down menu.
-Click on the Tools Tab.

Windows will give you a message that the disk can't be check because it is in use. Click yes to the prompt if you would like to schedule a check on the next reboot.

Go ahead and re-boot your pc and the check will begin.

This will cause Vista to check your file system entries on the MASTER BOOT TABLE against the hard drive to find any inconsistencies.

In the process it will correct the Boot Table accordingly.

Be patient, an HHD 300GB in size may take about 15 minutes.


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Search for huge files

You probably have a program that is creating huge data files. I use LTSpice and it easily creates data files well over 100 megabytes if the design isn't stable. Photo-editing software will create huge files if you change from JPG to the program's native file format.

Check for space-consuming files using the Search command.

Press the Windows Start button, then "Search" and "Files or Folders".
In the "Search Results" window, make sure "Look in:" is set to "Local Hard Drives", then click on "What size is it?".

Click on "Specify size (in KB)", leave the default "at least" and enter "100000" to list all files over 100 megabytes.

Click on "More advanced options", then make sure "Search subfolders" IS selected and "Search system folders", "Search hidden files and folders" and any other options are NOT selected.

Click on "Search" and wait a few minutes, then go through the list of results and see which files are eating up the space. You can either delete them in the Search Results window or just use the results to determine which program is creating the huge files.

Some poorly-written programs store data files in a folder under Program Files (which is a system folder) until you configure it to use another folder. If you don't find the offending files, repeat the search with "Search system folders" and "Search hidden files and folders" selected, but be careful about what you delete.

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2yr old harddrive blues

Gathering the central idea around these issues, your time trouble shooting your HD is futile, rather replace the drive(1Tb prices are ridiculously low & opt for a 32mb cache or 64mb costly but fast. Bottom line replace the drive and save yourself additional back up blues.

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possible fix but not garantited
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Disappearing Hard Drive
by mkarp57 / October 4, 2009 8:41 AM PDT


I am having the same problem with my laptop computer. What I
found out was that the OS ( Windows Vista ) is the problem. What
happens as was told to me is that when you do your hard drive clean-up
there are shadow copies along with your restore points taking up
hard drive space, and when you go and delete all but your current
restore points alot of times the shadow copies remain. Sometimes
they will be deleted with your restore points but not always. I
also am having a problem when switching between certain applacations
my screen will go dark for about 6 sec. before the screen reapears.
What I found out is on the desktop settings the option for Aero
was not working right. Again the OS (Vista) was the problem.I am
now waiting on Windows 7 to come out and completely remove Vista
from my computer. Hope this was of some help to you.

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hard disc space

run quick heal antivirus

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Freeing up your hard drive with tuneuputilities 2009.

Go to this web site and download and install this software. It is a 30 day free trial version with all the full function for you to try. It worked for me. Cause one day I had 845 GB left and when I used the software I had 890 GB so that is a huge jump for freeing up my hard drive. This software is easy to use also.

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Where O where has my disk space gone?
by throuwlin / October 4, 2009 11:24 PM PDT

This is a good question. With the home PC memory capacity ever growing tis increases the amount of disk space need to O/S house keeping. With a 32 bit system for simplicities sake we will say you have 4GB. This will increase the size of the page file and the size of the hibernation file. There is also a store for memory crash files and MS error reports, but Vista never crashes so they can't be taking much space. Happy

There are also bowser cache and temporary files. A quick look at my laptop that is rarely used for down loading and internet access has over 5GB in temporary files. There may also be files camping out in your recycling bin (Don't forget to take out the trash).

The last item that may be the most worrisome is that you may be unwittingly provided a file sharing service to joe hacker. Do a search for .zip and movie type files. If you discover such files that has no explanation you could be a victim of a hacker.

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Help! Hard-drive space doing the disappearing and reappearin

Try to view Hard Drive using Live CD Linux such as Ubuntu 8.04/9.04, Puppy Linux 4.3 (faster download) and Knoppix. Download for free.

Next may be you need to increase (sizing)hard drive where windows/linux is bootable, deleting temporary file and other before you sizing

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