File Upload Class - MIME type detection error - 2.1.0

[eluser]zwadder[/eluser]
I had the same problem and the suggested solutions didn't work. I had reports that DOCX, PPT and some other extensions wouldn't upload. I found out that all of these files had a MIME type of "application/zip", obviously the came out of a zipped archive, after making an array for the docx type in adding 'application/zip' to the docx mime type did the trick. Then I did the same for the other types and it all worked.
I think using this can be tricky because every file can be uploaded by first zipping it and unzipping it en renaming the extension to docx.