Can't stop continuopus rebooting after downloading an Avast update

Got a call from a friend with Avast caused problem. Last night she received a message that there was an upgrade ready for downloading so she proceeded with it. System shuts down and reboots continuously. I searched on this forum and found a number of such instances and the moderator and others suggested a restart in safe mode followed by uninstalling avast. Got her to do that but computer (running win XP with Embarq as her ISP) again continuously reboots even in safe mode so she can’t uninstall or anything. Any help would be appreciated. Jerry

Operating system restart needed by avast message - First check the contents of the C:\Program Files\Alwil Software\Avast4\Setup\setup.log file, which should show you why it thinks the reboot is needed.

This may be solved, in some systems, by deleting the file C:\Program Files\Alwil Software\Avast4\Setup\reboot.txt

If that doesn’t resolve it check this:
You can also check this registry entry (right after computer restart):
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager, if it contains “PendingFileRenameOpertaions”.

Check its contents and if there’s only “reboot.txt” from avast4\setup folder, delete PendingFileRenameOperations, don’t delete any other key.
Back-up (export) the registry key before you edit/delete, just in case.

Unfortunately she can’t get into any files. Restarted in safe mode but system just keeps re-booting every few seconds. Comments?? Suggestions??

Please, don’t post twice the same!
Just double the help effort.
My answer here http://forum.avast.com/index.php?topic=30374.msg250784#msg250784

Sorry I misread your original post, thinking it was avast requesting a reboot.

If the same thing is happening even in safe mode there is something more serious going on as avast doesn’t start in safe mode.

It could be a hardware failure, overheating (cpu fan not working) and causing a cut out or any number of things which could be causing a crash which results in a reboot. Normally you want the system to blue screen (BSOD) rather than reboot as this provides some information on the screen even though it is often difficult to interpret.

This is usually accessed through My Computer, View System Information,Advanced tab, Startup and Recovery, Settings button. Here you need to uncheck the Automatically restart option. The problem as I see it is She may be unable to get in to make these changes.

http://www.google.com/search?q=XP+continuously+reboots