[Dovecot] Problem with excel and word attachements ?

[Frank Bonnet]

Hello

We are in (random) troubles with some emails that contains
word and excel attachements ( others attachements are OK )

I don't really think Dovecot is implied in this trouble but I want
to be sure ...

The problem is users cannot open attachements from their clients
( thunderbird 3.1 ) it stays in "download" mode until timeout.

Maybe there is a Dovecot's workaround to solve that boring problem ?

Thank you