Question : Windows Logs off Immediately after Successful Logon - Faux partitions

After opening my PC up to air clean components and fans I reassembled and rebooted, logged on to Windows, but then it logs me right off.

I've reviewed http://www.experts-exchange.com/Operating_Systems/WinXP/Q_20796722.html and can access the registry from another machine.  A couple of twists:

My system drive letter has been E: for sometime.  After reassembling and upon the first boot, I got in, but my Dual Head Matrox card was only showing one screen, so I rebooted.  On next boot It went into ChkDsk mode, said it was looking at C: (which I don’t have), then I got the log on/log off problem.

-      Edited registry key Mounted Devices via remote machine.  Renamed E: to C: rebooted, logged in and got in OK.  But on next boot, get same problem (Logon/Logoff) and the problem stays until I edit the registry again.
-      Tried to do a Repair Install, but WinXP says no other Windows exists (but it does, on Disk0, Partition(1), ID1.  Most weird, is if I move to the next screen to do a fresh install, I see one valid partition and 6 non-existent ones.  Disk0 is valid, but Disk1~7 are not. All on the same ID1 (SCSI) and all the same partition(1) with 0 MB  space.  I did have 8 drive letters at some point.

-  Also, Window Logo stays on for much longer period of time than before the problem.

What gives?

Answer : Windows Logs off Immediately after Successful Logon - Faux partitions

Open the box.  Reseat cards and check all cables, reseat memory.
Boot the machine with the box open.  Watch the BIOS POST messages and coinfirm
memory and hard drives are recognized.  Use the PAUSE key to freeze the screen
so you can read it.  If you recognize a problem, try loading the BIOS defaults.
.
Confirm that all fans are working.  
If all look OK, boot  Safemode to access system restore and restore to a point b4 the trouble began.

Dave