False positive ONLY when copying to stick

I copied the skype version to a stick.
Each time it was detected as "Packet.win32.MUPX.gen@129019204
Only when copying.
No matter the heuristic level.

If its scanned direct with comodo, its clean!
Tested with malwarebytes and clam av as well. Also clean.

Hello clockwork,

Please submit the detected file as False Positive using the following link so we can check it:

Best regards,

Its larger than 30mb. How to do that?

Its the digital signed
.exe installer of that skyperversion.

Upload it to VirusTotal and put the link here.
Later they can harvest it from VT or ask you to share it.

It only happens with this file,
and only while being copied to a stick.

Hi clockwork,

This is to inform you that the reported file with SHA1 <3c444bfb2e94ae9e101b9528ed11d9416bbf0495> is not detected by AV database Version <20667> of COMODO Internet Security <>.
Please Update you AV database and scan it again.

Best regards

Scan comes up clean, like before.

It still gets detected as above when copying it to a stick. (Update 20669)

I copied other skype installers, nothing like that happens.