Firefox may be crashing or otherwise not closing properly if the session gets restored on the next start.

Make sure that Firefox closes properly and that there isn't a hanging Firefox or plugin-container process left in the task manager.

• "Firefox hangs when you quit it": https://support.mozilla.org/kb/Firefox+hangs

Try to use "Firefox/File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit") to close Firefox if you are currently doing that by clicking the close X on the title bar.

Thanks. It doesn't seem to make any difference by what means I close Firefox. It isn't crashing (as far as I am aware) and the task manager doesn't show the Firefox process or any plugin still running after it has closed. The tabs are restored even after the PC has been shut down and restarted. I suppose a reset of Firefox is an option but I'm reluctant to go down that route as my understanding is that plugins add-ons and extensions are all lost and it would take some time to get them all back. If it's likely to solve the problem I'll give it a go.

Hello Jonnyp62, see if the next helps : How to fix preferences that won't save

Corrupt or damaged prefs.js file

thank you

Thanks - Took me a while to try this. Renaming the file forced Firefox to create a new one when it restarted but the problem hasn't gone away. I have also tried disabling / uninstalling my "extra" toolbars but that has made no difference either

hi, see in about:config ,

the browser.startup.homepage is set to your homepage ?

the browser.startup.page is set to 1 (default) ?

do you have google as your homepage or another one ?

if you try the SearchReset add-on resets your search preferences and home page to their default values, and then uninstalls itself, if you have another homepage (like wikipedia) then you have to set your homepage again.

thanks

The browser.startup.homepage is set to my homepage. The browser.startup.page is set to 1. I use bbc.co.uk as my homepage. Running the SearchReset add-on made no difference. I appreciate the suggestions and will try anything else but it looks like a total rest might be the only option

What is the signature at the end of the sessionstore.js file?

• http://kb.mozillazine.org/sessionstore.js

It should show "session":{"state":"stopped"} to indicate that Firefox closed properly.

• "session":{"state":"running"}
• "session":{"state":"stopped"}

Sorry but I can't see a signature at the end of the file. Pretty sure I'm looking at the right thing (The JScript file) but there's nothing even similar to what should (or shouldn't) be there.

The past few days I've had this problem, and I've found the solution. Run system restore in Windows and restore to a date before the problem.

Thanks - That might have worked but I've just found that the disk space allocated to restore points had been set to zero. Changed it now but it means that I have no restore points created before today's