All e-mail messages coming as attachments

It is actually on my mom's computer and I went over last night to have a look at exactly what it is doing. It only started doing it yesterday morning and isn't quite as I described now that I have seen it for myself. Nothing new has been installed, either hardware or software wise.

When you go to the inbox in Windows Mail the e-mails all appear normal with no attachment paper clip beside them however when you select one of the e-mails nothing shows in the preview pane below and after a few seconds a paper clip will appear in the bar between the upper and lower panes and if you select it, it shows two attachments, one which is a .txt file and the other an html. If you select the html attachment it opens the e-mail and appears as any normal e-mail normally would except in an internet explorer window.

This applies to all e-mails even ones received some time ago that at the time would appear normally in the preview pane.

I have never seen anything like it and have no idea what caused it or how to fix it.

We both use Shaw as our e-mail provider. She has AVG and ran a scan the other day and I downloaded and ran Microsoft Security Essentials as well and neither of them showed any problems.

She had mentioned the other day that her e-mail was slow and I thought she meant it was slow when you hit send receive and that it took some time to download e-mail. What she actually meant was that when you click on an e-mail already in your inbox it took a while for it to diaplay in the preview pane. Now it is slow as well and when you click on an e-mail nothing displays in the preview pane and a paper clip all of a sudden appears in the bar between the upper and lower panes even though there is no paper clip beside the e-mail in the inbox as there tradionally would be if it came as an attachment.

I wondered if I should also post this is the virus forum as perhaps someone as seen this type of thing has a result of a virus of some type that the virus scan is not detecting, but was unsure if you are permitted to post the same problem in more than one forum?

Thank you