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How can I get rid of UXL so that I can run Firefox ?

  • 2 replies
  • 2 have this problem
  • 6 views
  • Last reply by cor-el

FrancN
FrancN
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When I try to start Firefox I get an error message "XULRunner, Error: Platform Version '20.0.1' is not compatible with 

  minVersion>=20.0
  maxVersion<=20.0"
    This error occurs with Version 20, I have had to go back to Version 18.
When I try to start Firefox I get an error message "XULRunner, Error: Platform Version '20.0.1' is not compatible with minVersion>=20.0 maxVersion<=20.0" This error occurs with Version 20, I have had to go back to Version 18.

All Replies (2)

patrickmc
patrickmc
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Hello FrancN,

This error will happen from time to time. The common solution is to do a clean install.

If you see the message, "XULRunner - Error: Platform version <x.x.x.x> is not compatible with minVersion <x.x.x.x>"" ("<x.x.x.x>" depends on version number), after a software update, use another browser to download the Firefox installer from mozilla.org/firefox, save it to the desktop or other location, delete the Firefox installation directory and then Reinstall Firefox .

If Firefox still does not start, see the Firefox will not start after updating section below.

Please let us know if this solves your issue.

Cheers, Patrick

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Note that this error is usually caused by security software like ZoneAlarm that is protecting files in the Firefox program folder and prevents Firefox from updating all files properly.
This leaves you with an inconsistent Firefox installation, so it is essential to delete the Firefox program folder before reinstalling Firefox.
If you still have problem then you may need to disable security software temporarily during the installation.