Hello again!
Are you or was you using Internet Explorer 8? If so, what version?
There are currently three versions of IE8 out on users' computers: Beta 1, Beta 2, and Release Candidate 1.
Also, do you have any updates installed for Internet Explorer 8. In Internet Explorer 8 RC1, the bug was fixed that if the user was to uninstall IE8 before he/she uninstalled the updates for it, that it would spawn off errors in the event viewer.
Here is my HMOS Error Report:
Userenv.dll corrupted, caused by Uninstalled Internet Explorer 8, any version
CF7639F3-ABA2-41DB-97F2-81E2C5DBFC5D -- corruption Identification
Message in Event Viewer: 'Windows cannot query DllName registry entry for {CF7639F3-ABA2-41DB-97F2-81E2C5DBFC5D} and it will not be loaded. This is most likely caused by a faulty registration.
******BUG******
When Beta 1 or Beta 2 of Internet Explorer 8 is removed, and the updates are not uninstalled first, these error messages appear in the Event Viewer.
This has been known to slow down the loading of Windows.
HijackThis identifies this commonly as:
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\GPExtensions\{CF7639F3-ABA2-41DB-97F2-81E2C5DBFC5D}]
Workaround or Solution Either re-install Internet Explorer 8, RC1 now, or you can try to run SFC /SCANNOW by using
this tutorial by Usasma System File Checker will be sure to find some missing DLLs and apply them in to their proper place.
If System File Checker fails to solve the problem and the user does not want to continue using Internet Explorer 8, then it is suggested to do a clean install of Windows.