Broken e-mail attachments

I use Microsoft Exchange at work, and Outlook Express at home, and have no trouble sending attachments from work to home or back(Powerpoint files Word files with graphics etc.) However,if I try sending attachments from work to others outside our “Global Mailbox”, the attachment doesn’t arrive or is unusable (can’t be opened). If I send the attachment to home, then to whoever, the attachment works fine. Is there some setting I have overlooked? I’ve been through the properties pages in Microsoft Exchange and didn’t see anything that looked promising. How can I fix this?

It might be sending it UUEncoded instead of MIME format. In outlook 98, menu Tools->Options->Internet E-mail tab, make sure the MIME radio button is set, and text encoding set to NONE. Outlook express at home may recognize the UUencoding, but others that you send to may not. Mime is the new standard.

Thanks but I don’t think that is all of it, I’ll just keep trying.