Since I have started using Windows Mail, I cannot open .EML, .WAV, .WMV, .MP3, .JPG, .JPEG or .GIF attachments. I have gone to the TOOLS/OPTIONS/SECURITY tab and:

1. Checked the 'Internet Zone(Less secure, but more functional)' box.
2. Unchecked the 'Do not allow attachments to be saved or opened...' box.
3. Unchecked the 'Block images and other external content in HTML email.' box.

Still no joy on solving this problem. What else am I missing here?

Solved the problem. It took a complete reinstall of the Vista OS. Apparently the upgrade on only 1 GB ram did not allow all files to copy over correctly. Performing a complete install using 2 GB ram did the trick.