If you have install 9.0.1 version, you have useragent problem, because your useragent tell us that you have 3.5.5 version (Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.1.5) Gecko/20091102 Firefox/3.5.5 ).

check the version in Help then About firefox, if you have 9.0.1 see how to fix user agent: in Websites or add-ons incorrectly report incompatible browser find Reset your user agent and follow the steps.

thank you

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Thank you so much for your reply and I followed your instructions as detailed, I still have a problem, I have copied the useragent field as I think something is not right but I don't know what to replace it with:

general.useragent.compatMode.firefox;false general.useragent.locale;en-GB I have checked the version of Firefox for XP and that is showing 9.0.1 as being current but I am still getting the message on my main home page as follows:

You're not on the latest version of Firefox. Upgrade today to get the best of the Web!

About Mozilla - Firefox Support What do I need to change , becasue i'm sure it's something to do with the user agent?

FOR : "You're not on the latest version of Firefox. Upgrade today to get the best of the Web! "

all you have to do is to set another page as the home page, see why is that in cor-el reply here .

thanks again