That information might help us.
One note: I recently ran into something similar to your issue regarding the "Windows Logon".. There are a number of malware programs which will rename the critical "winlogon.exe" file to something else like "winlogon2.exe".. The malware then replaces the renamed file with a trojan also named "winlogon.exe". So the "bad" winlogon.exe is working as a trojan while still allowing the "good/real" winlogon.exe to sit beside it.. (The "good/real" file has an icon which looks like a blue window with a yellow half-moon inside so it's easy to identify.)
In my case, I used the XP Recovery Console to scan through the files in C:\Windows\System32 and find both the bad and the good versions of the file.. I deleted the bad file from the Recovery Console and renamed the good file back to its original/correct "winlogon.exe".. Rebooting the computer allowed it to load Windows so I could run antispyware scans and finish cleaning up the computer.
It might be worth checking..
Hope this helps.
Grif
I?m 90% sure this is caused directly or indirectly by a virus I accidentally installed through a program I wasn?t suppose to install. First thing?s first here are my laptop specs:
Asus A8JP
C2D 2.0gHz
2GB RAM
Windows Vista Home Premium
ATI x1700 (catalyst 7.9 drivers)
So I ran the virus/Trojan program (not knowing it was, even though AVG warned me not to run?foolish move on my part) and a windows error window showed up saying something about needing to protect my computer and explorer.exe shut down along with other programs. So my computer restarts, I see the ASUS screen, then the ?windows is starting? screen. Then when it should get to the windows login screen, the screen is black and stays black after 5-10 minutes. If I vigorously move my mouse cursor while its starting up, the same black screen persists but I can now see the white mouse cursor and can move it around the black screen. Also when I press alt-tab I see 2 programs running and can alt-tab btwn the 2. One does not have a name (I?m presuming it?s the virus/Trojan program that?s preventing windows from starting up) and the other is named ?windows logon? so I?m guessing windows log-on is definitely running, but that unnamed program is preventing me from seeing the log-on screen or accessing the log on screen. So here are thigns I?ve tried (w/o any peripherals plugged into my laptop)
1. Safe mode starts up until the screen where the drivers/files are being loaded, and the ?please wait? screen, but right afterwards when its suppose to go into the desktop in safe mode, the machine restarts automatically in non-safe mode, brining back to the black screen I decribed before.
2. I inserted the windows recovery cd and can?t restore my computer to a previous restore point because I turned that feature off. I tried to automatic repair service but after the ?repair? I still get the blank screen.
3. I can use the command prompt via the recovery CD and have tried running ?chkdsk? which resulted in no errors. I also tried running ?sfc /scannow? but I get the message ?Windows File Protection could not be initiate a scan of protected system files?
I?m pretty confident the virus program has maybe indirectly or directly altered system files or display drivers so that I can?t access the log-in screen, or prevents me from booting into safe mode.
Is there any way I can boot from a USB disk drive that has a anti-virus scanning program I can run to rid the virus? Right now I can not even access safe mode nor the desktop, but can access my BIOS screen and the vista recovery CD.
I really hope to fix this blank screen problem w/o reformatting my hard drive as I have not backed up my personal files and do not wish to loose them. Thanks.

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