I got a call last night from someone with a fairly heavy accent claiming to be from Microsoft. They were calling to tell me that I had a virus and needed to go on my computer so they could show me where it was infected and how to fix it.
Microsoft is never going to call you on the phone to tell you that you have a virus and they probably aren’t going to send you to a non-Microsoft site to install a program so they can “help” you. Also, you should generally never give out financial information ( credit card number, bank account info ) to strangers who call you out of the blue.
Here is a link to Microsoft on the subject: Microsoft.com: Avoid Phone Scams
aaaannnd here’s a link to someone who played along with the scammer to see what would happen. ( It didn’t end well ): Phone scammers call the wrong guy, get mad and trash PC