This issue can be caused by the presence of leftover files in the Firefox program folder (defaults\pref) like a file firefox.js that overrides the update URL with a wrong link.

Do a clean reinstall and be sure to remove the Firefox program folder to remove the file(s) that cause the problem.

See:

• [/questions/826858]

See also comment 36:

• Bug 653830 - Popup notice Software Update - Update Failed - Something is trying to trick Firefox into accepting an insecure

From your answer, I would say the problem, if it is "left-overs", is probably on the XP and not on the Vista laptop. Thanks for your suggestion. I'll do as you advise.

Don't worry. The "something tried to trick Firefox" message is just badly worded. It really just means that Firefox failed to verify the update's certificate and consequently did not install it. Other discussions about that message seem to suggest that this happens quite frequently and is not, in fact, an indication of "something trying to trick Firefox", but a failure on the part of Firefox itself.

If the update was installed the second time then this time it did succeed in verifying the certificate, so the update is ok.

Thank you, tilmanschmidt. All seems well on the XP, and I appreciate your advise.

-> Run as Administrator

-> Software Update not working properly

• http://kb.mozillazine.org/Software_update#Software_Update_not_working_properly

Check and tell if its working.

Thank you. Helpful info.

So is your problem resolved now ??

This problem seems resolved. Thank you all for your help and suggestions.

Glad to hear it

Sorry. Didn't realize the "solved it" button was there. Shows how observant I am! Thanks again.