This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Error: Javascript Application: what happened:[Exception... "Component returned failure code: 0x80520012 (NS_ERROR_FILE_NOT_FOUND) [nsIFile.createUnique]" nsresult: "0x80520012 (NS_ERROR_FILE_NOT_FOUND)" location: "

  • 5 cavab
  • 201 have this problem
  • 1 view
  • Last reply by 6407

more options

When I double click on the Firefox icon, a box pops up heading Javascript Application and inside is the error message as detailed above. The box offers only one option "OK" and once I click on that the program works well. I access emails online and when I click on the respons button or to send a new email, the same error message pops up.

When I double click on the Firefox icon, a box pops up heading Javascript Application and inside is the error message as detailed above. The box offers only one option "OK" and once I click on that the program works well. I access emails online and when I click on the respons button or to send a new email, the same error message pops up.

All Replies (5)

more options

Seçilmiş Həll

more options

I solved my problem - it was an extension that was causing the problem, something called Ask Toolbar - after I disabled this, my Firefox is working 100%. Thanks for the advice!

more options

You're welcome

more options

The problem was caused by AVG's new security toolbar. Disabling it from add-ons has fixed the problem for me. Thanks for everyone's help. Hope this can help others. Larry.

more options

Had no problems until I "updated" to Firefox 4.0. Now have this irritating problem on every computer "Updated". How can I go back to older version of Firwefox?

THIS SHOULD HAVE BEEN LISTED IN "PROBLEM" SECTION ---

Modified by 6407