Problem Opening Files

[shades]

Recently, I have been receiving the following message when attempting to open certain Word and Excel files:

Windows cannot open this file

To open this file, Windows needs to know what program created it. Windows can go online to look it up automatically, or you can manually select from a list of programs on your computer. What do you want to do?

- Use the Web service to find the appropriate program

- Select the program from a list"

This occurred on a few files saved to my desktop, which I have now reassociated with the correct program. But this also happens when I have an attachment. Usually, I have the option to Open (from current location) or Save. The only option, other than Cancel, that I have is Save. What is the reason for this and how do I correct it?

Could this be related to Adware? What about the fact that I am trying a new Virus scanning software (F-Secure) and perhaps I clicked on Deny when I should have clicked on Accept? It may not be a big deal since I can still download the files and open them later, but I would like the option to open them without having to save it first. Please advise.

Thanks,

Dave