[Evolution] attachment not visible

["dragomrak freenet de" <dragomrak freenet de>]

Hello,

at first I have to apologizie for my English. I am from Germany and the
time when I spoke English often is a some years ago and so my English
is a bit untrained. So I have to apologize for some mistakes, which I
will surely make. :-)
The problem I have is that Evolution does not show an attached file
sometimes. When I open that mail with e.g. Thunderbird, the attachment
is visible. Almost all attachments work fine, only sometimes there is
one, which does not work and will not be displayed.

How can I solve that? Many thanks for your help.

Kind regards, Catweazle