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keep getting "add-on does not match the add-on firefox expected" message

  • 6 replies
  • 174 have this problem
  • 11 views
  • Last reply by swbitton

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Since I updated to Firefox 6 I have not been able to add new or replace old add-ons (firebug). When I click any add-on to download from the add-on panel I keep getting a download error message; when I am on the actual add-on page in firefox and click the install button I get a box at the address bar that reads "The add-on from addons.mozilla.org could not be installed because it does not match the add-on Firefox expected"

Since I updated to Firefox 6 I have not been able to add new or replace old add-ons (firebug). When I click any add-on to download from the add-on panel I keep getting a download error message; when I am on the actual add-on page in firefox and click the install button I get a box at the address bar that reads "The add-on from addons.mozilla.org could not be installed because it does not match the add-on Firefox expected"

All Replies (6)

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Some add-ons can produce this error if there is a problem with the calculated hash in the Add-ons site. This can be fixed on the site, but we need to know about it. Please send a message to amo-admins@mozilla.org explaining the problem and the add-on that gives you this problem.

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Some add-ons? I just tried to update two existing add-ons (FoxTab and RSS Ticker) and got the message and then tried to get some new add-ons (ColorZilla and Download Statusbar) to no avail.

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If this is happening for all add-ons, then the problem is most likely not on the site. We would have certainly heard from many users if those very popular add-ons had incorrect hashes calculated for them.

It sounds like there's something corrupting your downloads and making the hash comparison fail.

Have you tried downloading the file (right click -> save as) and then dropping it directly in the Add-ons Manager?

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Make sure that your security software isn't inspecting and repacking the extension file.

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Login as admin and install. Worked for me ;)

edit: Actually, I had to install it as admin and then I was able to install it as a regular user as well.

Modified by foxyfoxy

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I am able to install add-ons directly from the owners websites if they have them but not from Mozilla's add-on page.