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After downloading, I get a setup message saying that I need to restart my computer -- doing so -- the message comes up again and again

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That has happened for some months. I have been getting along with other browsers.

I click on Mozilla Firefox to load it. I get the message Your computer must be restarted to complete the previous upgrade of Firefox. Do you want to restart now?

This AM I did a new download of Firefox from the Internet. When it completed, I get the same issue. The same Setup message. My computer has been restarted and I still get the message.

Thank you for your help. Bill

That has happened for some months. I have been getting along with other browsers. I click on Mozilla Firefox to load it. I get the message Your computer must be restarted to complete the previous upgrade of Firefox. Do you want to restart now? This AM I did a new download of Firefox from the Internet. When it completed, I get the same issue. The same Setup message. My computer has been restarted and I still get the message. Thank you for your help. Bill

All Replies (2)

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You do not need to restart the computer when installing Firefox.

Make sure you only download Firefox from http://www.mozilla.org.

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One possible cause for this error message is that files in Firefox's program folder have become locked. In that case, Firefox may suggest that you restart Windows since that usually will clear file locks. If the locks keep returning, it could be that they are enforced by your security software.

One workaround is a "clean reinstall", meaning you rename the Firefox program folder and run the full installer again, without uninstalling. This should leave your settings undisturbed. However, if you are a cautious person, you might make a backup of your settings folder, or at least your bookmarks.

(1) Back up settings or bookmarks (optional)

On Windows 7 (or Vista or 8/8.1), you can paste this into the Start menu search box, or into the address bar of a Windows Explorer window:

%APPDATA%\Mozilla\Firefox\Profiles

That should open a folder that contains one or more folders that have a semi-randomized name. If there are multiple folders, back up the most recently updated one. If you are in a hurry or have limited space on your backup media, drill down into the folder and back up the subfolder named bookmarkbackups.

(2) Download the full installer for Firefox from

https://www.mozilla.org/firefox/all/

Scroll down to find your preferred language and operating system.

(3) Rename the Firefox program folder

On Windows 7 (64-bit), that would be this folder:

C:\Program Files (x86)\Mozilla Firefox

Rename it to something like

C:\Program Files (x86)\OldFirefox

(4) Now run the installer. It should automatically detect your settings folder and have you back up and running.


After this "clean reinstall" process, you may discover that you are missing a plugin or two. Some installers drop their plugins into the Firefox program folder instead of keeping them in their own folders. To hunt these down, check:

C:\Program Files (x86)\OldFirefox\Plugins
C:\Program Files (x86)\OldFirefox\browser\plugins


Any luck?