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Firefox will not open - intermittent - Windows10 pro

  • 3 replies
  • 3 have this problem
  • 2 views
  • Last reply by FredMcD

MonaNot
MonaNot
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Once I click on the icon to run the Firefox browser I momentarily get the little blue icon of wait... then nothing. I can use everything else on the computer including Edge, IE, Chrome and Safari.

If I go to the Task Manager it shows Firefox with no activity. I can invoke a number of instances of Firefox all doing the same thing... nothing.

If I end all the instances of Firefox in the task manager, then try to run Firefox again it opens and works normally. I can run a number of instances and they all work as they should.

If I normally close all the instances of Firefox, they may or may not run the next time I attempt to run Firefox ( intermittent ). If the browser does not run, I repeat the process of ending the Firefox in the task manager then reopening it... it will then run.

I have tried doing a clean install of Firefox without luck. Same problem. The Windows 10 pro (64bit) fresh install

I have another laptop with Windows10 with the same Firefox addons and the same imported bookmarks etc. It works fine. 

This is puzzling?? Any suggestions would be appreciated.

Thanks, Peter

Once I click on the icon to run the Firefox browser I momentarily get the little blue icon of wait... then nothing. I can use everything else on the computer including Edge, IE, Chrome and Safari. If I go to the Task Manager it shows Firefox with no activity. I can invoke a number of instances of Firefox all doing the same thing... nothing. If I end all the instances of Firefox in the task manager, then try to run Firefox again it opens and works normally. I can run a number of instances and they all work as they should. If I normally close all the instances of Firefox, they may or may not run the next time I attempt to run Firefox ( intermittent ). If the browser does not run, I repeat the process of ending the Firefox in the task manager then reopening it... it will then run. I have tried doing a clean install of Firefox without luck. Same problem. The Windows 10 pro (64bit) fresh install I have another laptop with Windows10 with the same Firefox addons and the same imported bookmarks etc. It works fine. This is puzzling?? Any suggestions would be appreciated. Thanks, Peter

Chosen solution

Hi Fred,

Thanks for your quick response. I tried your suggestion, but it didn't work, but you got me thinking... thanks.

What I did do... I uninstalled Firefox and then removed all references in the window registry related to Firefox. I then set the Edge as the default browser, rebooted. I then downloaded and did a fresh install of Firefox, and set it as my default browser. Rebooted just to be sure.

Yay! It works now.

Read this answer in context 👍 0

All Replies (3)

FredMcD
FredMcD
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Start Firefox. If the FF window does not show up, right click the Firefox icon on the task bar, and select Open New Window. If this works, close the first window.

You may have a corrupt xulstore.json file. https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved

MonaNot
MonaNot Question owner
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Chosen Solution

Hi Fred,

Thanks for your quick response. I tried your suggestion, but it didn't work, but you got me thinking... thanks.

What I did do... I uninstalled Firefox and then removed all references in the window registry related to Firefox. I then set the Edge as the default browser, rebooted. I then downloaded and did a fresh install of Firefox, and set it as my default browser. Rebooted just to be sure.

Yay! It works now.

FredMcD
FredMcD
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That was very good work. Well Done.