Welcome to the forums,

Some more detail about o.s
path to the file etc would be helpfull.

as a first course, have you tried AdAware S.E. and Spybot on your system as this might be caused by installing some software such as WeatherBug

Do a search to see if any of these files are on your system

C:\WINDOWS\system32\addwj32.exe
C:\WINDOWS\system32\iexw32.exe
C:\WINDOWS\system32\mfcde32.exe
C:\WINDOWS\winbl32.exe
C:\WINDOWS\System32\bbbfr.exe