Firefox, Thunderbird, Interner Explorer issues

Win 7, SP1 running on a tower with an EVGA motherboard.
Hi,

On my tower at my desk I seem to have a problem with both firefox(FF) and thunderbird(TB)!
Here it is: For several days now I have not been able to run either TB or FF. When I click on either one, I get an error msg that states:

"Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system"

So I call up msconfig.exe and find no 'program' or 'process' that would interfere with TB or FF. I open up 'Services' and nothing installed as a service.

So, now I think "Virus". So I run Zonealarm AV and it reports 'no virus'. I install Comodo AV and it reports no Virus. The same for housecall.trendmicro.com.

I have installed and reinstalled both TB and FF 4 times now and there is no change to that message. Now let's talk about Internet Explorer. When I open either 32bit or 64bit I get the following:
"A program on your computer has corrupted your default search provider setting for Internet Explorer. Internet Explorer has reset this setting to your original search provider, (www.bing.com). Internet Explorer will now open Search settings, where you can change this setting or install more search providers"

I have uninstalled all firewalls and antivirus programs and there is no change.

Now all I can think of is 'rouge toolbar'. And it is hiding way up in the troposphere where I can not see it and it is out to get me!

Anyone that can point me to new actions to take would be appreciated!

fb2

Check that Firefox isn't listed in the Task Manager processes.

As a temporary workaround try this:
Open the "Run" box (or the you can use the Start Menu search box) and try typing:

Firefox -no-remote

There is a space between the "x" and "-".

Have a look at these articles too.
http://support.mozilla.org/en-US/kb/...not+responding
http://kb.mozillazine.org/Profile_in_use

lehnerus2000 has posted good info on the FF problem, so I will add some info for IE. Have a look here:

Internet Explorer 8 restores the search provider settings when the "Prevent Internet Explorer Search box from displaying" Group Policy setting is enabled

Or for IE9 try deleting the file mentioned as the Answer in this thread (note the need to Show hidden, and unhide OD files as mentioned by Mushaf a couple of posts below)

IE9: A program on your computer has corrupted your default search - Microsoft Community

You may be well served to run the System File Checker and see if it finds any issues to correct.

SFC /SCANNOW Command - System File Checker

A Guy

If you think that a faulty add-on or rogue toolbar is causing your problem, try starting Firefox in "Safe Mode".

Tutorial
Firefox - Start Firefox in "Safe Mode"

Good to hear that your problem has been solved.
Thanks for reporting the solution that worked for you. :)

For future reference:
You should create a backup HDD image, BEFORE tinkering with your System Permissions and other settings.

Windows has a built-in backup tool, but I use Macrium Reflect (Free) to create my images.

Tutorials
Backup User and System Files
Imaging with free Macrium