No worries. I wouldn't like to see you have to format the drive if there's a solution at hand. The only thing I can honestly think of is to search the hard-drive and also the Registry for anything that relates to the application.
The best start would be checking the Registry key HKLM > Software to see what the exact name is for the program's entry. Then search the Registry for this value, deleting any you come across
Remove it from Program Files and also check Document & Settings\Application Data and for all the user accounts. Also check Program Files\Common Files.
The Registry can be accessed by going to Start > Run type
REGEDIT
Before making any alterations, see
[here] for instructions on backing up the Registry.
If you are not comfortable with editing the Registry, firstly acquire the name of this program in the Registry, as stated above. Download the attached and compressed file. Execute the script and enter into the textbox the value you have just acquired, then perform a search. A textfile will appear once complete, for which you can attach to this thread in and I will rewrite it so as to remove those entries that need to go.
Regards,
M_M