Sherri, and there could be many causes. Here are a few;
1] Memory. With 256MB of RAM you may struggle to run XP. Increasing the RAM to, say, 512MB will help.
2] Hard disk. You didn't say what size HD you have, but if it is small, (say, 20GB), then XP will struggle.
3] Viruses and spyware. You say you have an anti-virus, but do you use a firewall? Also, what do you do about spyware and adware? Malware, (in general), will slow your computer down.
4] Installed programs loading at startup. Check your startup files, (Start > Run > type in ''msconfig'', (without the quotes), click OK), and in the Startup tab, untick any programs that are not necessary to run at startup. Anything that you can just double click an icon on your desktop to run it, or in the Start menu > All programs, do not need to be loaded at startup.
5] Running processes. If you open the Task Manager, (right click the Taskbar, select Task Manager), and click on the Processes tab, check to see if you have any background processes running that you do not need. Use this web site to check each process;
http://www.answersthatwork.com/Tasklist_pages/tasklist.htm
Any you do not need running, goto Start > Run, services.msc, and disable or set to Manual the services you want to change. Be sure about these. Disabling the wrong ones can render your Windows unusable.
6] Windows Updates. Now you have upgraded to Windows XP, make sure you have all the Windows Updates needed.
7] A few tips; Goto this thread, created by Griff Thomas in the Computer Newbies forum;
http://reviews.cnet.com/5208-6121-0.html?forumID=45&threadID=22053&messageID=238454
It is a ''very'' long thread, but there is loads of information there about options to keep your computer running clean and smoothly.
Good luck.
Mark
We have a Dell 8100 Series, Pentium 4 Processor,
1.7 GHz, 256 MB PC800 RDRAM.
We upgraded from Windows ME to Windows XP several months back. It works much better now than it did when we ran the ME but, very often, it is quite slow. I notice that when I run a virus scan there are a lot of undo/backup files. I assume this is from the upgrade and they are ME files?
How can I make our system faster?

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