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Firefox 54, windows 7 pro 64, can no longer set Firefox as default browser - Multiple installations

  • 4 replies
  • 2 have this problem
  • 9 views
  • Last reply by nsmith17044

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I have 3 different Windows 7 PCs that are now exhibiting the same problem. All started this week with version 54 update. I cannot get Firefox 54 set as the default browser. It will ask to set as default every time firefox is started.

I was running McAfee EPS but have completely un-installed and McAfee support now indicates this isnt' caused by McAfee since it isn't deployed. No other security software is installed on any of the machines effected.

I have tried un-installed in normal mode and in safe mode. I've tried deleting all profiles and restarting. I've tried manually deleting all Mozilla folders on all user profiles after the un-installs (many different folders and locations found). I've run ccleaner after the un-installs to ensure things are cleaned up. I've rebooted before the re-installs. I've always run install with 'run as administrator'. The user accounts already have local admin level security.

Firefox does NOT show up in default programs (see attached image). It hasn't starting this week when this problem started after v54 starting getting updated. I am typing this question in Firefox 54 and it does function.

I've been searching and searching for other things to try but don't understand what is happening that Firefox available to be set as a default.

Please help provide a solution as this is really causing productivity issues and I really don't want to migrate to Chrome.

I have 3 different Windows 7 PCs that are now exhibiting the same problem. All started this week with version 54 update. I cannot get Firefox 54 set as the default browser. It will ask to set as default every time firefox is started. I was running McAfee EPS but have completely un-installed and McAfee support now indicates this isnt' caused by McAfee since it isn't deployed. No other security software is installed on any of the machines effected. I have tried un-installed in normal mode and in safe mode. I've tried deleting all profiles and restarting. I've tried manually deleting all Mozilla folders on all user profiles after the un-installs (many different folders and locations found). I've run ccleaner after the un-installs to ensure things are cleaned up. I've rebooted before the re-installs. I've always run install with 'run as administrator'. The user accounts already have local admin level security. Firefox does NOT show up in default programs (see attached image). It hasn't starting this week when this problem started after v54 starting getting updated. I am typing this question in Firefox 54 and it does function. I've been searching and searching for other things to try but don't understand what is happening that Firefox available to be set as a default. Please help provide a solution as this is really causing productivity issues and I really don't want to migrate to Chrome.
Attached screenshots

Chosen solution

SOLVED: After trying the un-install / re-installs on the other machines with no change, I realized the default Firefox deployment was installing the 32bit version. After un-installing and then installing the 64 bit version, the problem was resolved on all 3 machines exhibiting this problem.

Maybe the deployment should be defaulting to the 64bit version of Firefox for the 64bit version of windows?

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All Replies (4)

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Additionally, I have also tried the 'Set Program access and computer defaults' custom option with the Firefox option set. None of the options here have any effect on this. I've tried different options here.

Manually associating file types such as .htm / .html to the firefox.exe in program files (x86) / mozilla firefox folder does not fix this as desktop and folder bookmarks are URLs.

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Chosen Solution

SOLVED: After trying the un-install / re-installs on the other machines with no change, I realized the default Firefox deployment was installing the 32bit version. After un-installing and then installing the 64 bit version, the problem was resolved on all 3 machines exhibiting this problem.

Maybe the deployment should be defaulting to the 64bit version of Firefox for the 64bit version of windows?

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It should not make any difference as which version of Firefox you are running as both 32 & 64 run on 64 bit windows.

Could you please come back and mark this post as solved. Thank You.

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@ pkshadow, That might have been the case up to this point but clearly that is no longer true. Three different machines all having the same problem starting with version 54 seems to point a new problem with the deployment. I have 22 other machines on that network that had no problem with the update. They all look to be running the 64 bit version.