Windows XP: opening email attachments

opening email attachments

First off, I'd be remiss if I didn't say the following:

Never, ever, blindly open e-mail w/attachments. And even if you know and trust the sender and are expecting an attachment from them and know what that attachment is, you should always perform a virus scan at the very least.

Anyway, going on to your question. What does "Windows cannot open this file without a program to run it" mean? Not to sound snide, but it means exactly what it says: you're trying to open a file that Windows doesn't know how to handle, either because that filetype has no installed application to be associated with it or because no association to the filetype has been made to an installed application.

On to the second question: How do you know what program will open it? Well it depends on what the filetype is, which you didn't happen to mention. What is the filename? What is the file extension (the extension is the three letters after the period in the filename, such as ".exe", ".jpg", and so on)? If you're not familiar with a filename's extension and/or what program it goes with, you can do a Google search for it, or go to http://filext.com/ and look it up there.

Again, just so it's said: Be VERY careful when opening attachments in e-mail. Make sure you have anti-virus and make sure it's up-to-date, and if it's possible, set it to scan your e-mail for you upon reciept. I have AVG Free and it does this.