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How do I get Firefox to work on my computer again? Uninstalled and reinstalled restarted twice.

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A soon as i select a second window after launch, Firefox immediately says" not responding". I have used Firefox for years on this pc. Is it a virus that only affects Firefox?

A soon as i select a second window after launch, Firefox immediately says" not responding". I have used Firefox for years on this pc. Is it a virus that only affects Firefox?

Chosen solution

Could you implement the Flash workarounds I mentioned in my first reply and then try exiting out of Firefox and starting it up normally (not in Safe Mode)?

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All Replies (9)

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Niemo said

A soon as i select a second window after launch, Firefox immediately says" not responding".

How are you selecting the second window -- for example, opening a bookmark or search result?

Does it make any difference whether you open that page in a tab versus a separate window?

Does the "Not Responding" last for more than 60 seconds?

We do have a general article on "not responding" issues: Firefox hangs or is not responding - How to fix.

Since Flash can cause non-responsiveness problem and is used pervasively through the web, I suggest the following to minimize potential issues with Flash during your troubleshooting:

(1) To avoid unnecessary pain on sites where Flash is not actually essential, try setting Flash to Click-to-Play ("Ask to Activate"). This will delay Flash from starting on a page until you approve it.

To set "Ask to Activate", open the Add-ons page using either:

  • Ctrl+Shift+a
  • "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. Look for "Shockwave Flash" and change "Always Activate" to "Ask to Activate".

With this setting, when you visit a site that wants to use Flash, you should see a notification icon in the address bar and usually (but not always) one of the following: a link in a dark gray rectangle in the page or an infobar sliding down between the toolbar area and the page.

The plugin notification icon in the address bar typically looks like a small, dark gray Lego block. (If it's red, Flash needs updating.)

The delay in activating Flash can help distinguish between problems caused on initial page load, styling, and script activation vs. loading/running Flash.

If you see a good reason to use Flash, and the site looks trustworthy, you can go ahead and click the notification icon in the address bar to allow Flash. You can trust the site for the time being or permanently.

But some pages use Flash only for tracking or playing ads, so if you don't see an immediate need for Flash, feel free to ignore the notification! It will just sit there in case you want to use it later.

(2) A common cause of unresponsive script errors on Windows Vista and higher is the protected mode feature of the Flash player plugin. That feature has security benefits, but seems to have serious compatibility issues on some systems. You can disable it using the Add-ons page. Either:

  • Ctrl+Shift+a
  • "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. On the right side, find "Shockwave Flash" and click the More link. Then uncheck the box for "Enable Adobe Flash protected mode" and try that for a day to see whether it helps.

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As soon as i hit ctrl-shift-a , firefox becomes non-responsive.

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Hmm, could you test in Firefox's Safe Mode? In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement? (More info: Diagnose Firefox issues using Troubleshoot Mode)

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Came up otion to restore- clicked and immediately non-responsive.

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Niemo said

Came up otion to restore- clicked and immediately non-responsive.

I'm not sure what you mean by option to "restore". Usually you would get a small panel with the choices of open in Safe Mode or do a Refresh. Can you try again and see whether you get that box?

Or did Firefox show the option to restore a previous session after you started in Safe Mode?

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Yes, i got into safe mode and then it offered the restore or close option.

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Was a list of previously open tabs and the option to either restore some or all of those tabs, or to start a completely new session? And neither of those gets around the freeze?

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I left it for awhile and it cleared up, so i opened another tab and went surfing. So, what do i do for a permanent fix- not in safe mode?

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Chosen Solution

Could you implement the Flash workarounds I mentioned in my first reply and then try exiting out of Firefox and starting it up normally (not in Safe Mode)?