Does a Firefox button appear on the task bar, or is it completely invisible?

If the button appears, Firefox might be opening offscreen. For that problem, check out the steps in this thread: opens off monitor screen.

If nothing appears, Firefox may be hanging before it is showing the UI. Could you try starting Firefox in its Safe Mode? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

With firefox.exe not running, hold down the Shirt key when launching Firefox.

A small dialog should appear. Click "Start in Safe Mode" (not Reset).

Any luck?

i was not able to open in safe mode, since to do that, firefox has to open in the first place...( i was using chrome, which works just fine, to be in this help forum)

I ended up "fixing" the problem by creating a new profle, then just moving my book marks back.

i just might stick with using chrome. now that i have tried it. i find i like it. but its good to have FF working again, in the event chrome blows up on me at some point in the future.

And BTW, thanks for the very quick and easy to follow response; even tho it was not the fix I needed, i do thank you for the response just the same.

BTW , I failed to answer you question; starting in the safe mode with shift key did not open Firefox, the only fix was to create a new profile.

Sounds good.

Since you know how to move bookmarks, you probably could move other relevant data if you wish (details on what is in the different file: Recover important data from an old profile).

If you discover problems with the new profile after shutting down and restarting Windows, there could be some external process running that is causing this problem (whether injecting an add-on or modifying a file).

Thanks for that information. I was trying to move the saved passwords file, but while the instructions are clear... since the instructions lead me to the new profile only..not how to copy files from the old profile ( or perhaps they did and i didn't see it) I think I'll just skip that step and just enter them manually as visited websites ask for them. .