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Update does not clear Registry of previous version

sludge7051-x
sludge7051-x
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. . . HISTORY

2/18/14 . . . Two versions of FF need to be installed? 26 and 27 | Firefox Support Forum | Mozilla Support https://support.mozilla.org/en-US/questions/986898

I'm using Win 8. I was looking at Programs, and saw that I had two versions of Firefox installed, 26 and 27. I un-installed 26 (because I had 27), and then, when I went to launch FF, I got the error message: "Could not load XPCOM," and, it wanted to delete the Shortcut. I did a System Restore - and that didn't fix it. I downloaded the current version of FF, 27.0.1, installed over what had been Restored, and that fixed it. Isn't it confusing to have more than one version of the browser installed?

3/18/14 I just installed 28.0, and see that 27.0.1 is there. 28.0 installed over 27.0.1 . . . Did 28.0 un-install 27.0.1, and just not accurately reflect this in the Registry?

If you installed over it, then the previous version has been replaced. If you're running the 32-bit version of Windows 8 and you have an English (US) version of Firefox, then the aforementioned registry key is the one you want to delete:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Mozilla Firefox 27.0.1 (x86 en-US)

. . . CURRENT

10/20/14 I was not able to delete this in the Registry key, so I just de-installed / re-installed FF. I have not seen this with any other program. Please see screenshot.

. . . HISTORY 2/18/14 . . . Two versions of FF need to be installed? 26 and 27 | Firefox Support Forum | Mozilla Support https://support.mozilla.org/en-US/questions/986898 I'm using Win 8. I was looking at Programs, and saw that I had two versions of Firefox installed, 26 and 27. I un-installed 26 (because I had 27), and then, when I went to launch FF, I got the error message: "Could not load XPCOM," and, it wanted to delete the Shortcut. I did a System Restore - and that didn't fix it. I downloaded the current version of FF, 27.0.1, installed over what had been Restored, and that fixed it. Isn't it confusing to have more than one version of the browser installed? 3/18/14 I just installed 28.0, and see that 27.0.1 is there. 28.0 installed over 27.0.1 . . . Did 28.0 un-install 27.0.1, and just not accurately reflect this in the Registry? If you installed over it, then the previous version has been replaced. If you're running the 32-bit version of Windows 8 and you have an English (US) version of Firefox, then the aforementioned registry key is the one you want to delete: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Mozilla Firefox 27.0.1 (x86 en-US) . . . CURRENT 10/20/14 I was not able to delete this in the Registry key, so I just de-installed / re-installed FF. I have not seen this with any other program. Please see screenshot.

All Replies (3)

sludge7051-x
sludge7051-x Question owner
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Screenshot

cor-el
cor-el
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  • Top 10 Contributor
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You will have to do a clean reinstall of the current release.

You can find the full version of the current Firefox 33.0 release in all languages and for all Operating Systems here:

It is best not to uninstall Firefox in cases like this, but removed the registry keys from no longer installed versions, either manually or via some registry cleaning software. In some case the uninstall key isn't updated properly and multiple version show in the Windows Control Panel although only the most recent version is installed.

sludge7051-x
sludge7051-x Question owner
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Thanks!

I had no problems un-installing both of those - and then installing the offline-install version.

I thought I would lose my Add-ons and bookmarks, but thankfully, they were still there. So FF really is an intelligently designed program. I wonder why it has an issues as basic as this.