Download the Mozilla Search Reset {web link} This add-on is very simple: on installation, it backs up and then resets your search preferences and home page to their default values, and then uninstalls itself. This affects the search bar, URL bar searches, and the home page.

Thanks for your suggestion but it had no affect on the problem. I installed it, noted it had loaded (using the Add-on Manager), then saw it uninstall. No change to the Manage Search Engines list. I also have a minor roblem with the URL search bar in that when I type a link into the box it does not go to the webpage but there is no problem using bookmarks. Are these issues related?

You said you had ad-ware? Some are known to hang around.

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!

Fred, thanks. I should have said I use Microsoft Security Essentials. I added Malwarebytes recently and detected some adware stuff - most of which it removed but Speedial keeps coming back after starting up which is why I tried Ad-Aware (to nil effect). Oh, I also used MS Safety Scanner. I'm beginning to think my only option is to reinitialise my machine and reload my software (2-3 days wasted!!)

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.