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In firefox 4 RC, some addons installed suddenly disappear, but checking the profile, some of the missing addons related files are still here, how to make the addons back?

  • 2 replies
  • 42 have this problem
  • 1 view
  • Last reply by uekilake

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I use firefox 4 form beta 9 to RC (zh) now and there are also firefox 3.6 installed in computer. One day when I open Fx 4 RC, some (actually a lot but not all) of the adoons just disappear. When I check on about:addons page, some addons installed do not appear in the list.

The addons REMAINED including:

  • addons I already used in Fx 3.6 (like webmail notifie , xmarks)
  • addons only can use in Fx 4 (like Open Web Apps for Firefox).

The addons DISAPPEARED including:

  • addons I already used in Fx 3.6 (like yoono)
  • addons installed when using Fx 4 (like updatescanner, Thumbnail Zoom).

But when I check the profile(by Help > Troubleshooting Information>Open Containing Folder) , some (not sure is it all) of the missing addons related files are still here [lucky], so any one know how to make the missing addons back?

Some more details:

  • This happened when i use RC for already a few days and keep on even i restart Fx and windows.
  • The bookmarks, history, search engine and even themes and icon setting are still here. [ I only sync bookmarks but not history for both xmarks and firefox sync.]
  • This addons are really disappeared but not disable only!
  • This number of addons missed, as i remember, at least 30, should be more than that number bacause some of them are installed but in disable mode.
  • I try to install back one of the addons - Stylish, the installed code are still here.
  • It is nearly an impossible mission to install every missing addons again, as it really kill my time.
I use firefox 4 form beta 9 to RC (zh) now and there are also firefox 3.6 installed in computer. One day when I open Fx 4 RC, some (actually a lot but not all) of the adoons just disappear. When I check on about:addons page, some addons installed do not appear in the list. The addons '''REMAINED''' including: * addons I already used in Fx 3.6 (like webmail notifie , xmarks) * ''addons only can use in Fx 4'' (like Open Web Apps for Firefox). The addons '''DISAPPEARED''' including: * addons I already used in Fx 3.6 (like yoono) * '' addons installed when using Fx 4'' (like updatescanner, Thumbnail Zoom). But when I check the profile(by Help > Troubleshooting Information>Open Containing Folder) , some (not sure is it all) of the missing addons related files are still here [lucky], so any one know how to make the missing addons back? Some more details: * This happened when i use RC for already a few days and keep on even i restart Fx and windows. * The bookmarks, history, search engine and even themes and icon setting are still here. [ I only sync bookmarks but not history for both xmarks and firefox sync.] * This addons are really '''disappeared''' but not disable only! * This number of addons missed, as i remember, at least 30, should be more than that number bacause some of them are installed but in disable mode. * I try to install back one of the addons - Stylish, the installed code are still here. * It is nearly an impossible mission to install every missing addons again, as it really kill my time.

Modified by uekilake

All Replies (2)

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Delete the files extensions.* (extensions.rdf, extensions.cache, extensions.ini, extensions.sqlite) and compatibility.ini in the Firefox profile folder to reset the extensions registry. New files will be created when required.

See "Corrupt extension files": http://kb.mozillazine.org/Unable_to_install_themes_or_extensions

If you see disabled, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left side of the Search Bar to do a compatibility check.

Modified by cor-el

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I try it (move the file away from the profile) but when opening firefox again , just some message box appear and then Fx 4 crash down. And open Fx 4 again and same things happen. Then I paste back the file and open Fx 4, I found some setting are lost, like the icon position but it did make a few addons back like New tab king, but still a lot of them are missing, How to do?