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"side-by-side configuration is incorrect" cannot load or uninstall

  • 2 replies
  • 2 have this problem
  • 20 views
  • Last reply by hogarm

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Have been using Firefox for a long time with no problems. Windows 10, 64 bit. Today, I tried to open Firefox and received the immediate message "the app has failed to start because its side-by-side configuration is incorrect ... " Trying to uninstall and then reinstall, went to uninstall, and it will not run, get the same error message. went to Mozilla and tried to download a new copy of Firefox, received the same error message both in trying to run and in trying to save. Can't do most of the fixes, because I cannot open a copy of Firefox.

Have been using Firefox for a long time with no problems. Windows 10, 64 bit. Today, I tried to open Firefox and received the immediate message "the app has failed to start because its side-by-side configuration is incorrect ... " Trying to uninstall and then reinstall, went to uninstall, and it will not run, get the same error message. went to Mozilla and tried to download a new copy of Firefox, received the same error message both in trying to run and in trying to save. Can't do most of the fixes, because I cannot open a copy of Firefox.

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This can happen because of missing or corrupted Visual C++ installation This issue can be caused by a corrupted or incomplete Visual C++ installation (multiple versions can be installed side-by-side; SxS)

Microsoft Visual C++ Redistributable for Visual Studio 2017 (link at bottom of the page)

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Thanks for the info. However it didn't work. When I tried to run it, I received the same message. "... app failed to open ..." etc. I have discovered another program that isn't working. It quite evidently is a Window problem and not a Firefox problem. I will go there for help. Thank you, very much, again.