The a4s2_f.dll error message is an issue with a process of the SFG MFC application; an error has occurred while this program has attempted to access a DLL file in your computer’s registry. This may be a simple registry error (a missing or damaged file) or it may indicate the presence of a virus on your computer. The way to differentiate involves finding the location that a4s2_f.dll is running from.
The easiest and most thorough way to determine the precise location of this file and find other error messages is to have your computer scanned. One registry error usually means that more will follow. Have you had trouble with access violations, Internet browser errors, blue screen errors, and other things that affect day-to-day computer usage? These things are easily fixed by first scanning your computer to isolate the errors and then using ZookaWare PC Cleaner, the most complete registry cleaning software available, to restore your PC’s registry files.