Key is the full version installer and delete the folders.

uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files and C:\Program Files(x86) Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 57.0.3 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

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Well, that worked - but.........

Everything was working just fine with 57.0.2 and it stopped after the 57.0.3 update.

What you suggested worked but it seems like taking a sledge-hammer approach ---- why uninstall everything, clean files, restart, re-install, reconfigure, etc.

It still doesn't answer the question of why safe-mode worked and even with no extensions installed, would not work after the 57.0.3 update.

Roxie2401 said

Well, that worked - but......... Everything was working just fine with 57.0.2 and it stopped after the 57.0.3 update. What you suggested worked but it seems like taking a sledge-hammer approach ---- why uninstall everything, clean files, restart, re-install, reconfigure, etc. It still doesn't answer the question of why safe-mode worked and even with no extensions installed, would not work after the 57.0.3 update.

To your info it is because the New FF version updates based on your O/S version be it x86 or x64 if you update Online. So those that ran a x86 FF comes to be surpised when the FF installed is x64 FF and they loose most connections to it. So this is why if you don't want conflicts is to download x64 FF for a x64 Windows O/S but don't delete the older x86 FF folder and only delete it after you installed the x64 FF and ran it to configure it. Then you can go back and delete the empty x86 FF of any remaining old version to insure there are no more conflicts. This is what I did when I found out the hard way. But this is what I did by Trail and Error to figure this out.

Roxie2401 said

Well, that worked - but......... Everything was working just fine with 57.0.2 and it stopped after the 57.0.3 update. What you suggested worked but it seems like taking a sledge-hammer approach ---- why uninstall everything, clean files, restart, re-install, reconfigure, etc. It still doesn't answer the question of why safe-mode worked and even with no extensions installed, would not work after the 57.0.3 update.

Is a matter of opinion after a refresh you have to set everything up again. After a uninstall as I said to you your Profile is Saved. Nothing to setup again as everything was in the Profile and you obly replaced Folders for new Folders and a Stub installer that downloads the files vs a full version installer that you have the file. Not so much of a chance of packet/s lost in download or corruption.

Both have a chance to fix it. I just think myself this is not so messy and is fast and if still issues then can start on Extensions and Profile as well.

I hope that explains the rational behind it. Also would have got 57.0.4 instead of 3 and if not got up date to fix security issue : https://support.mozilla.org/en-US/kb/update-firefox-latest-version re : https://www.howtogeek.com/338269/a-huge-intel-security-hole-could-slow-down-your-pc-soon/

Please let us know if this solved your issue or if need further assistance.

Roxie2401 said

It still doesn't answer the question of why safe-mode worked and even with no extensions installed, would not work after the 57.0.3 update.

Possibly the update corrupted something.

To see a list of other things that are disabled in Firefox's Safe Mode, for future reference: http://kb.mozillazine.org/Safe_Mode