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Firefox locked up with this message: Exception caught Fnc: navigate Error: (More).

  • 3 replies
  • 3 have this problem
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  • Last reply by FredMcD

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Running an email program in Firefox with Windows7. It locked up and gave the following message about JavaScript: Exception caught Fnc: navigate Error:[Exception... "<no message>" nsresult: "0x805e0006 (<unknown>)" location: "JS frame :: chrome://saff/content/saffplg.js :: oSAPlg.navigate :: line 281" data: no]

Clicked OK and it seems to be running okay. Is there any reason for concern?

Running an email program in Firefox with Windows7. It locked up and gave the following message about JavaScript: Exception caught Fnc: navigate Error:[Exception... "<no message>" nsresult: "0x805e0006 (<unknown>)" location: "JS frame :: chrome://saff/content/saffplg.js :: oSAPlg.navigate :: line 281" data: no] Clicked OK and it seems to be running okay. Is there any reason for concern?

Chosen solution

An e-mail program, or at an e-mail provider web page?

Issues have been previously linked to the McAfee Site Advisor extension. Try to disable it and see if the problem persists.

http://service.mcafee.com/faqdocument.aspx?id=TS100162 How to uninstall SiteAdvisor

To disable it: Type "about:addons" in the Location bar Find the extension and click on its "Disable" button


Many site issues can be caused by corrupt cookies or cache.

  • Clear the Cache and
  • Remove Cookies
    Warning ! ! This will log you out of sites you're logged in to.

Type about:preferences<Enter> in the address bar.

  • Cookies; Select Privacy. Under History, select Firefox will Use Custom Settings. Press the button on the right side called Show Cookies. Use the search bar to look for the site. Note; There may be more than one entry. Remove All of them.
  • Cache; Select Advanced > Network. Across from Cached Web Content, Press Clear Now.

If there is still a problem, Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.

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Chosen Solution

An e-mail program, or at an e-mail provider web page?

Issues have been previously linked to the McAfee Site Advisor extension. Try to disable it and see if the problem persists.

http://service.mcafee.com/faqdocument.aspx?id=TS100162 How to uninstall SiteAdvisor

To disable it: Type "about:addons" in the Location bar Find the extension and click on its "Disable" button


Many site issues can be caused by corrupt cookies or cache.

  • Clear the Cache and
  • Remove Cookies
    Warning ! ! This will log you out of sites you're logged in to.

Type about:preferences<Enter> in the address bar.

  • Cookies; Select Privacy. Under History, select Firefox will Use Custom Settings. Press the button on the right side called Show Cookies. Use the search bar to look for the site. Note; There may be more than one entry. Remove All of them.
  • Cache; Select Advanced > Network. Across from Cached Web Content, Press Clear Now.

If there is still a problem, Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.

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Fred, Cleared cache and cookies. Problem is gone. Thanks for your help!

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Glad to help. Safe surfing.