That file was found by Avast Home Edition. I just couldn't find anything on it, good or bad, so I thought I would post it to see if I could get some feedback. That was one of many items found when doing a boot-time scan via Avast.
Also, I don't know enough about what should and what should not be in the Windows folder.
If Avast comes up with it as a bad file, kill it, it does not sound like anything usefull. API is a real term though, and I'm sure many applications use that word in their files, but your specific file does not turn up anything usefull and a few api files in Windows are marked as known viruses.
About what lives in the Windows folder, because Windows is such an open system, it's hard to say what files you will find in there especially once you start installing applications. Asking here or just doing a web search on the file will get you an answer though.