What Is This Pup?

[ask100]

Using a Viao laptop and Windows 7 Malwarebytes keeps finding this pup.
Any member know what this is:
C:\users\Howard\AppData\Roaming\Mozilla\Firefox\Profiles\x3caufdz.default-1361055449200\prefs.js
I hope I haven't made an error in that!
Is is serious?

[Tuvok]

If it keeps finding it then that implies to me that if you've removed it its coming back.

Scan and clean again with Malwarebytes. Before restarting the computer turn off system restore - some nasties reload them selves from system restore.

After you've restarted do anothe scan. Only when the scan comes back clean do you then turn back on system restore.

[ask100]

Thanks for your suggestion.
I just looked at System Restore but was a unable to see how I can turn it off. Can you help please?

[Tuvok]

http://windows.microsoft.com/en-gb/windows/turn-system-restore-on-off#1TC=windows-7