what is octet-stream

Occasionally when I visit links on ebay or go to google, I get the following popup application/octet-stream and then it asks me to save it in another application. If I click it again, everything is fine. But it only happens in firefox. Is this an avast thing or something else?

XP sp3/avast internet security/firefox 3.6.15/ie 8

application/octet-stream is a MIME type. Not avast really.

P.S. You should update your FF to 3.6.16 due to a critical security issue with Comodo Certificates!

Thanks. What’s a comodo certificate? I saw firefox just came out with a version 4.0.

You must the the only one who missed the story. ;D

http://forum.avast.com/index.php?topic=74516.0

Thanks for the info.