Sending e-mails from Outlook-Where did my attachments go?

This is driving me nuts! Every time I send an e-mail (Outlook not express)to a couple of friends the attachments get stripped or arrive in his inbox (AOL) as 'winmail'!!! Is it a problem at my end or the other end, loads of other people get them OK except this guy and anoher chap wher the attachments are stipped off! Going through the net I have found this fantastic site of people who actually know about this stuff!!!Thank-you IT-GOD!

I've seen this problem from a friend sending email to me. I'll have to ask him
how this got resolved .....

I really appreciate the help, look forward to your post.........

my correspondant has since moved to using yahoo email for spam filtering.
The configuration that seems to work is:
tools->options
mail format tab->settings; click MIME
->International Options; choose Western European (iso)
btw: while Outlook has nice features (I use it all the time), you ought to move
to an email reader like Thunderbird for your own safety and security.

Thanks for your time and help, I really appreciate it.
Like your correspondent my set up is Yahoo feeding into Outlook, I was using Hotmail but it would only feed to Outlook Express. I only use Outlook as, in my own little pool of ignorance, it was the only way I could quickly and cheaply 'brand' my emails ie:richard@so-and-so .com and work from home. Do you think its Yahoo stripping attachments?
As to protection- do you think that Yahoo plus a firewalled router are enough to keep the world out?