Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

• Microsoft Safety Scanner
• MalwareBytes' Anti-Malware
• TDSSKiller - AntiRootkit Utility
• Hitman Pro
• ESET Online Scanner

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us!

That is considered to be Malware. See this for removal information.
http://www.mindspark.com/main/toolbar-info/remove-mws/index.shtml

Here's another one. http://www.ehow.com/how_4780067_rid-mywebsearch-toolbar.html

Thanks for advice but I can't find the one I have. I just uninstalled "ask toolbar" in case it was the problem but no go. The site or browser or search engine that I have is simply called, 'websearch' not "mywebsearch' and comes up as my home page but gives me the option of using google with it's own address bar. The people who own it call themselves 'Websearchinc.net' I have googled them and even zeroed in on the house they run it from. But I can't find anything about it being installed some how on my pc.`I used to get firefox as my home page ad it seemed to replace that. On Internet properties general tab, Home page in box says: Http://go.microsoft.com/fwink/p/?LinkedId=255141 if I type that into an address bar, I get a ninesmsn Homepage-Outlook.com That confuses me as it says is my default home page and yet I get this Websearch comes up as my home page. Don't know what to do to remove it nick890

Finally removed 'conduit' and 'websearchinc' and got my old firefox browser back. What I did was to run my Malwareebytes did a full boot scan and found that conduit and Websearch were hidden in 'ask.com' and Flv runner. was able to disable them. Took a couple hours and stuffed up my internet connection which then also took a while to sort out but now have a clear browser and a choice of safe search engines

So thanks for your input. Matter fixed