See http://kb.mozillazine.org/Corrupt_localstore.rdf

sorry, I delted RDF File then deleted Firefox & reinstalled Same Prob.

But had to reload all add-on   Tonyatfox

Thanks for your help cor-el--BUT--it did'nt seem to help my problem I have also deleted firefox & reinstalled same--but when reinstalling firefox picks up some info from the last time--so you have same fault

Did you find the Firefox profile folder?

Help > Troubleshooting Information > Profile Directory: Open Containing Folder

Yes I did & deleted same--to no avail!!

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).

• Don't make any changes on the Safe mode start window.

See:

• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems
• Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.

• Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
• Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")