I got one of these calls last night. I've had 7 or 8 other calls from at least 4 different numbers. Always between 10:15 and 11:15 p.m., background noise like a call center, always south Asian accents. Called my phone company about it. They said that they are scammers operating out of India, using the internet to call on different US phone numbers. Because they are not in the US, the phone company and the FBI can't touch them. On other forums, some people suggest not answering, others suggest that hassling the caller ends the phone calls. When they said they were calling about Windows, I asked them why the caller ID didn't say Microsoft? She said that Microsoft wouldn't call me about this. I asked her then why should I trust her. She told me I didn't have to trust her. I asked her, "How's the weather in India, Scammy Mc Scamface?", but she cut me off at "McScam".