Many virus scanners respond to cab and msi files. Mine does all the time. This is a sign of a good scanner. That's about all.

Be sure you download from an actual microsoft site. Do not use download sites other than microsoft. If you use an actual microsoft download site it is unlikely the download contains any viruses.How do you know it actually is microsoft you are downloading from?

If you start from this link it is likely microsoft hosts the download: http://msdn.microsoft.com/vstudio/express/

Then the only way someone can pretend to be microsoft is if they have hacked your internet service provider.

If you do not trust me you can choose to save the download and then scan it with your antivirus solution. If it still thinks it is a virus let us know.