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Firefox was fast when I first started using. Now, very slow to open and freezes often. Frequent message is "Warning-unresponsive script". Do I need to switch back to Internet Explorer?

  • 7 replies
  • 121 have this problem
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  • Last reply by Xircal

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Switched from Internet Explorer because seemed slow. Firefox was fast at first. Then upgraded to Firefox 4 and frequently have trouble opening. Sometimes page doesn't open, or is very slow. If I try to open again I will get Mozilla Firefox Unresponsive or a message that say "Warning-Unresponsive Script". Often have to restart and do the whole thing again. Don't really want to switch back to Internet Explorer, but getting tired of taking a half hour to get into my emails!

Switched from Internet Explorer because seemed slow. Firefox was fast at first. Then upgraded to Firefox 4 and frequently have trouble opening. Sometimes page doesn't open, or is very slow. If I try to open again I will get Mozilla Firefox Unresponsive or a message that say "Warning-Unresponsive Script". Often have to restart and do the whole thing again. Don't really want to switch back to Internet Explorer, but getting tired of taking a half hour to get into my emails!

All Replies (7)

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Try running Firefox in Diagnose Firefox issues using Troubleshoot Mode. If it functions properly in that configuration, then one of your add-ons is the culprit.

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Thanks, I'll try that. But why can't Firefox work with add-ons if they are available?

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Mozilla is addressing that problem right now actually. They recently published a list of the worst offenders even: Slow Performing Add-ons

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Thanks, but I don't have any of these add-ons. I am also not highly skilled with computers, so I don't really know how to check all possibilities.

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You can check for updates to add-ons in both the Extensions menu as well as Plugins by going to Tools | Add-ons and then clicking the icon at the top of the page next to the Search field.

Also, a regular visit to the Plugins Check is well worthwhile. Older versions can also cause slowdowns in performance.

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I am having the same problem, but not sure what's causing the slow down. Restarting in safe mode fixes the performance problem... but disabling all plug ins and extensions in normal mode (and restarting firefox) still shows the bug. Any ideas?