Recent answers to Unable to open a second firefox window if i have already a firefox window runninghttps://support.mozilla.org/en-US/questions/7654292010-11-19T22:27:59-08:00Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is 2010-11-19T22:27:59-08:00cor-elhttps://support.mozilla.org/en-US/questions/765429#answer-118269<p>Start Firefox in <a href="/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode" rel="nofollow">Diagnose Firefox issues using Troubleshoot Mode</a> to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools &gt; Add-ons &gt; Themes).
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<ul><li> Don't make any changes on the Safe mode start window.
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<p>See <a href="/en-US/kb/troubleshoot-extensions-themes-to-fix-problems" rel="nofollow">Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems</a> and <a href="/en-US/kb/troubleshoot-issues-with-plugins-fix-problems" rel="nofollow">Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems</a>
</p>thanks for the reply.i tried following the steps and did every thing.but i still cant open a second 2010-11-19T15:52:44-08:00FiSh_23https://support.mozilla.org/en-US/questions/765429#answer-118232<p>thanks for the reply.i tried following the steps and did every thing.but i still cant open a second window.
</p>You have a corrupted Firefox 3.6.12 user agent (Firefox/2.0.0.14):
Mozilla/5.0 (Windows; U; Windows 2010-11-19T13:08:28-08:00cor-elhttps://support.mozilla.org/en-US/questions/765429#answer-118224<p>You have a corrupted Firefox 3.6.12 user agent (Firefox/2.0.0.14):
</p><pre>Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.12) Gecko/20101026 Firefox/2.0.0.14
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<p>See * <a href="http://kb.mozillazine.org/Resetting_your_useragent_string_to_its_compiled-in_default" rel="nofollow">http://kb.mozillazine.org/Resetting_your_useragent_string_to_its_compiled-in_default</a>
</p><p>Check the <b>general.useragent</b> prefs on the <b>about:config</b> page.
You can open the <i>about:config</i> page via the location bar, just like you open a website.
Filter: <b>general.useragent</b>
If any <i>general.useragent</i> prefs are bold (user set) then right-click that pref and choose <i>Reset</i>.
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<p>Are you starting Firefox with the -no-remote command line switch?
</p><p>Make sure that you do not start Firefox with the -no-remote switch or have set the environment variable MOZ_NO_REMOTE=1 (Control Panel &gt; System &gt; Advanced &gt; Environment variables).
</p><p><a href="http://kb.mozillazine.org/Opening_a_new_instance_of_Firefox_with_another_profile" rel="nofollow">http://kb.mozillazine.org/Opening_a_new_instance_of_Firefox_with_another_profile</a>
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