What page is opening? The default 9-thumbnail page? Some other page?

Extensions can override your selections for new tab, home page, and search provider. Try reviewing and disabling nonessential, recently installed, or unrecognized extensions here:

orange Firefox button (or Tools menu) > Add-ons > Extensions category

Make sure you got no software that protects home page settings. There are such programs.

If you do not keep changes after a restart then see:

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

the default page is open after i changed to my home page ... it is the same as before ... no change at all... i checked there is only one pref.js file in rn7s7yyq.default folder... i do not think i had the software to protect the homepage ... any suggestion?... it works in my mac ... i did the same procedures and it works in my mac but not in windows pc... any help to correct this issue... cheers,

Do you have any tab-related extensions that might be overriding the built-in setting? You can review your extensions here and either disable them or try their Options buttons:

orange Firefox button (or Tools menu) > Add-ons > Extensions category

i found there is a addon extension called firefox home page 0.9.11 being installed ... i myself never installed this addon extension ... do not know exactly why it was installed ... i disabled & removed this addon extension and things get back to normal that i can set the new tab page open to my home page ... thanks for the help... cheers,