MP4 & flv files don't play on Windows apps (Solved)

[megapix]

Completely crazy! !

After reinstalling 5.7.1 on the USB now downloaded files play OK on Win 7

As I deleted the 'defective' files there's no way to find out what was behind the error messages.

For now all's well that ends well - until (if) it screws up again.

Thanks for all the advice.

Megapix