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Missing file on startup of firefox

  • 2 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

bschreur
bschreur
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This is the error I get when starting Firefox:

"File not found Firefox can’t find the file at jar:file:///C:/Program Files/Mozilla Firefox/browser/omni.ja!/chrome/en-US/locale/branding/browserconfig.properties. Check the file name for capitalization or other typing errors. Check to see if the file was moved, renamed or deleted." 

How can I fix it?
This is the error I get when starting Firefox: "File not found Firefox can’t find the file at jar:file:///C:/Program Files/Mozilla Firefox/browser/omni.ja!/chrome/en-US/locale/branding/browserconfig.properties. Check the file name for capitalization or other typing errors. Check to see if the file was moved, renamed or deleted." How can I fix it?

Chosen solution

The browserconfig.properties file was used in older Firefox versions to set a localized homepage. This has been changed in Firefox 63 to have support for non-localized homepages, so seeing a reference to this file is likely a leftover from an older Firefox version.

You can check the browser.startup.homepage pref on the about:config page and reset this pref to the default value.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

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All Replies (2)

Helder Magalhães
Helder Magalhães
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"How can I fix it?"

Unfortunately, it seems like either your Firefox install got corrupted, there's a external application preventing the file to be accessed (usually an anti-virus) or even an actual harddisk failure or filesystem problem (less likely).

Going through the first guess (the other ones are harder to diagnose and provide remote assistance), I recommend reinstalling Firefox. This seems related with the application itself so reinstalling will not remove any of your user data (bookmarks, extras, etc.).

If that doesn't work:

  1. check your security software - mark Firefox as a trusted application if needed
  2. go to that directory (C:\Program Files\Mozilla Firefox\browser) and check if the file omni.ja exists; if so, try to copy it to some other location
  3. post back the results

Good luck!

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Chosen Solution

The browserconfig.properties file was used in older Firefox versions to set a localized homepage. This has been changed in Firefox 63 to have support for non-localized homepages, so seeing a reference to this file is likely a leftover from an older Firefox version.

You can check the browser.startup.homepage pref on the about:config page and reset this pref to the default value.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

Modified by cor-el