If you do not keep changes after a restart or otherwise have problems with preferences, see:

• http://kb.mozillazine.org/Preferences_not_saved

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: "3-bar" menu button or Tools > Add-ons > Appearance
• Do NOT click the "Refresh Firefox" button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

cannot locate the prefile to try and correct - have the one download for new tab override - but the other one that I was told to download does not look as though it did.

You can use this button to go to the current Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox

Thanks - have tried several of the suggestions - and still only homepage opens - and new tab still shows all the tiles. clear all - state blank page, and open last tabs next time. Thanks again. not sure what else can do.

I did find the folder with the prefs.js files - alot had #'s - deleted those and named prefs.jsold and restarted ff - still same problem. Thanks again.

Hi ginnpr, let's review your settings on the Options page:

(1) General panel:

When Firefox starts: Show my windows and tabs from last time

(2) Privacy panel:

change to: Firefox will: Use custom settings for history

[__] Always use private browsing mode (unchecked) [XX] Remember my browsing and download history (checked)

For "Clear history when Firefox closes" either:

[__] Clear history when Firefox closes (unchecked)

Or click the settings button and make sure that "Browsing & Download History" is NOT checked so it does not get cleared at shutdown.

If that all checks out, an extension or external utility program might be removing your session history file, or Firefox might not be saving it in the first place...

Thanks - on one line you said to CHECK browsing and download history and on another you said to not CHECK - tried both ways and still nothing saves. This has only started happening since update to FF for version 47.0. Thanks

ginnpr said

Thanks - on one line you said to CHECK browsing and download history and on another you said to not CHECK - tried both ways and still nothing saves. This has only started happening since update to FF for version 47.0. Thanks

Okay, here's what I meant:

One checkbox is to remember history and one checkbox is to clear history, so my instructions are to say YES to remember and NO to clear.

If you say YES to clear, then you need to go into the Settings for that feature and say NO to clearing history. It's okay to clear cache, but clearing history will remove session history.

Hopefully that clarifies what you need for settings.

Hi - did this and still only homepage opens not email also, and new tab still shows all the tiles - on the option page now what I put in for open tabs when signing on keeps changing - so not really sure what the problem is. Thanks for you help

Normally Firefox saves those settings into the prefs.js file in your currently profile folder and reads them at startup. Some reasons that might fail:

(1) Firefox is not able to update prefs.js -- as with the prefs-1.js files you found before. Is that problem still happening? You might need to rename prefs.js to prefs.bad in that case to break the cycle.

(2) There is a user.js file in your profile folder that Firefox reads at startup, and uses to override your previous session settings. There is a specific section of the above article (How to fix preferences that won't save) on this problem.

(3) External security/privacy/utility software may be modifying Firefox settings files. One example is Advanced SystemCare, and there are others that block changes to your home page, for example, and other settings.

Note: By default, Windows hides the .js file extension. I suggest showing all file extensions unless it really bothers you, since then you have a clearer idea of which files are which. This article has the steps: http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions

Hi - did open the folder again and prefs file showed log in at 3:04 renamed bad and restarted - new prefs file showed log in at 3:22 and every time I log in the time changes so not sure what the problem is. Thanks again. Guess will have to live with it this way.

what are my options on uninstalling FF and do a reinstall - what will I lose for settings etc. Thanks

Hi ginnpr, how much do you want to lose?

Normally, the Firefox uninstaller leaves your profile folder intact on the assumption that you may well be reinstalling a different version of Firefox soon. This is why we say uninstall-reinstall doesn't resolve most issues.

On the other hand, if you use Revo or another tool, the data might all be completely removed and you would be starting from scratch. In that case, best to back up the files in your profile folder. These article might help:

• Back up and restore information in Firefox profiles
• Recovering important data from an old profile

But perhaps it would be simplest to try this three-minute experiment:

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox and start up in the Profile Manager using the Windows XP "Run" dialog (from the Start menu). Type or paste the following and press Enter to run it:

firefox.exe -P

This should open a small dialog -- don't delete anything here!

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like June2016, and ignore the option to relocate the profile folder. After creating the profile, select it and start Firefox in that profile.

Try setting your home page and modifying the new tab page, exit Firefox, and start it up again. Are settings saved in the new profile? If that works, you could migrate over some of your important data from the old profile to the new one.

When using the Profile Manager in the future, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

Hi - just entered the firefox.exe -P in the run - cannot locate firefox.exe. Thanks for all of your help once again.

That's a strange message. Is Firefox installed in an unusual location? If it's in the standard location, you could try using the full path:

"C:\Program Files\Mozilla Firefox\firefox.exe" -P

For readers on 64-bit Windows, you would use:

"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -P

Tried that and it does not work - also, the pref.js the date and time modified changes everytime I log on, the user.js has a date of 5/20/2015. Thanks again.

It can't find firefox.exe even with the full path, or it didn't launch the profile manager? Note that all Firefox windows need to be closed before you can launch the profile manager.

Firefox 47 now has an internal page called about:profiles which has a "Create a New Profile" button. I haven't tested it myself, but if you type or paste about:profiles in the address bar and try that button, can you create a new profile that way?

Hi - did this and have logged on an off at least 1/2 dozen times and seems to be working - did not lose anything - I think the reason could not locate firefox.exe is because on my system it is listed as mozilla_firefox.exe. Thanks again. Great help.