Outlook Express – Can’t open attachments

A customer is running Windows 98SE and is using
Prodigy.net as an ISP. Have updated Internet
Explorer to 6.0 with SP1 and Outlook Express
to 6.0. Has no problem opening e-mail, but
cannot open attachments. Difficulty may have
started after Prodigy was purchased by Yahoo!
and then Yahoo! was purchased by another company.
Customer is not certain of this. Any help would
be appreciated.