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I deleted some apps in Firefox 4 b2, opened 3.6, closed 3.6 and opened FF 4 again. But now it's presenting a series of very severe problems.

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After doing what I described in the thread title, Firefox 4 presented the following issues: 1- Tabs would not close. 2- The "forward" and "back" button would not be lit or clickable, as if I didn't visit any websites. Although pages did load, I could not go back and forth between them via these buttons. 3- the "feedback" button in the right-hand side of the screen was completely gone. Trying to download the respective feedback app that Mozilla provides didn't work, it wouldn't download. 4- the App Management screen would not open. 5- I did not save any of the pages from the previous session. They did appear in Firefox 3.6, wich appears to be functioning normally. The apps I had removed in FF4 were also removed in 3.6. So basically my FF 4 got completely messed up. Reinstalling it did nothing. Cleaning the registry with Registry Mechanic was to no avail either. I had to uninstall FF4 since it was unusable.

This happened

Every time Firefox opened

== When I deleted some apps in FF4, opened 3.6, then opened 4 again

After doing what I described in the thread title, Firefox 4 presented the following issues: 1- Tabs would not close. 2- The "forward" and "back" button would not be lit or clickable, as if I didn't visit any websites. Although pages did load, I could not go back and forth between them via these buttons. 3- the "feedback" button in the right-hand side of the screen was completely gone. Trying to download the respective feedback app that Mozilla provides didn't work, it wouldn't download. 4- the App Management screen would not open. 5- I did not save any of the pages from the previous session. They did appear in Firefox 3.6, wich appears to be functioning normally. The apps I had removed in FF4 were also removed in 3.6. So basically my FF 4 got completely messed up. Reinstalling it did nothing. Cleaning the registry with Registry Mechanic was to no avail either. I had to uninstall FF4 since it was unusable. == This happened == Every time Firefox opened == When I deleted some apps in FF4, opened 3.6, then opened 4 again

All Replies (4)

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Hmm, interestingly my Firefox version was automatically identified as of the Megaupload toolbar wich I deleted long ago. No wonder Youtube doesn't recognize me as having Firefox 3+ even though I use it. Some corrupted registry of that toolbar might be what is causing that.

Additionally I have long removed (or don't remember ever using) most of the plugins that were listed.

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a Mozilla page taught me how to fix the Megaupload problem, and Youtube now properly recognizes me. It wasn't a corrupted registry at all. One less problem down.

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Your UserAgent string in Firefox is messed up by another program that you installed. http://en.wikipedia.org/wiki/User_Agent

type about:config in the URL bar and hit Enter If you see the warning, you can confirm that you want to access that page. Filter = general.useragent. Right-click the preferences that are bold, one line at a time, and select Reset, Then restart Firefox

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Yes edmeister, as I have added in the replies, I have fixed this issue already. But thanks for trying to help about that one.

I scarcely believe that the User Agent string would cause all those problems in Firefox 4 though, it must be something else. Any ideas?