• get fresh installer from getfirefox.com
• remove Firefox completely
• run a clean install and try

I tried this and got the same box telling me I needed to reboot. I can't remove firefox at all.

Remove the Firefox program folder (C:\Program Files\Mozilla Firefox\) before installing that newly downloaded copy of the Firefox installer.

• It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.

Your bookmarks and other profile data are stored elsewhere in the Firefox Profile Folder and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.

• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/Profile_backup

I have the exact problem. Partly because my computer will not allow me to delete the Mozilla Firefox program folder.

Try to boot Windows in Safe mode (press F8 on the boot screen) to see if that allows to delete that folder.

See also:

• http://www.emco.is/products/move-on-boot/features.php - MoveOnBoot

I've deleted old directory, rebooted again and again, reinstalled Firefox and still get stuck in endless loop.

If files already have been downloaded then remove the files in the updates and updates\0 folder.
You can also delete active-update.xml and possibly updates.xml (stores the update history).

• http://kb.mozillazine.org/Software_Update (Software Update not working properly)

Windows XP:

C:\Documents and Settings\<user>\Local Settings\Application Data\Mozilla\Firefox\Mozilla Firefox\updates
(%USERPROFILE%\Local Settings\Application Data\Mozilla\Firefox\Mozilla Firefox)

Windows 7 and Vista:

C:\Users\<user>\AppData\Local\Mozilla\Firefox\Mozilla Firefox\updates
(%LOCALAPPDATA%\Mozilla\Firefox\Mozilla Firefox)

You can also check the VirtualStore folder (%LocalAppData%\VirtualStore) for pending files.

BEFORE READING THIS PAGE:

Windows XP. I'd done the usual things to upgrade from FF9 to FF10. I was in the reboot infinite loop with jess032.

I did a Windows uninstall on FF9 & deleted the FF9 and FF10 download files from my download folder. When I then tried to do a fresh FF10 install, the "reboot to complete a previous installation" message kept pre-empting it.

AFTER READING THIS PAGE:

I dragged-and-dropped the Mozilla Firefox program folder in toto to the recycle bin. (Instead of trying to delete it in situ.)

Then I did a fresh FF10 download, and it worked fine. Fervent relief.

P.S. Thanks, Mozilla, for telling me I'm awesome when I opened my account. Wikipedia said the same thing when I sent them some money, so it must be true. :-)

Deleting the whole folder solved the problem. Thankx (but it is not too elegant way of update a progrem...) Chalie