Thanks, and sorry for the Multiposting. But the problem was that I realised
afterwards that I posted my question in the wrong newsgroup. On my Vista PC
I use Windows Mail (not Outlook Express). The Junk e-mail folder was
automatically installed with WindowsMail. Up to now I can't find any setting
that indicates that mails sent by Apple MAC users are not trusted. Even when
I set the MAC sender as trusted,the next time that I get a mail from this
sender I get it again in my Junk e-mail folder.