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Firefox will not start: "Application has failed to start because its side-by-side config. incorrect. Please see application event log for more details"

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  • 6 have this problem
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  • Last reply by cor-el

Patatrack
Patatrack
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On a Windows Vista laptop. I have reinstalled Firefox, scanned for virus, malware, spybot etc... when I try to open Fierfox I get the above message. the rest of the computer is running fine.

On a Windows Vista laptop. I have reinstalled Firefox, scanned for virus, malware, spybot etc... when I try to open Fierfox I get the above message. the rest of the computer is running fine.

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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This seems to be caused by a corrupted Visual C++ installation (multiple versions can be installed side-by-side; SxS).
You can try to use the sxstrace.exe tool to see if you can find which files are missing or corrupted and (re)install missing Visual C++ libraries.

See: