Windows 7: Weird phone call 'from Microsoft' after re-activation

Hi,
I had to change from 32 bit to 64 bit today. After about 5 hours I get a phone call from some foreign guy going on about 'Microsoft Software Warranty'. After about 10 minutes I asked what it would cost and said I didn't want it. Thought it was suspicious the whole time and was googling for info while talking.

I assume this is a scam and if so how on earth would they know I just re-formatted?

Some idiots may be on the same ISP as yours, scanned it and got your OS.
Also, there are many web plugins that say what browser, windows and version you are using.

Nothing to worry about, just make sure you have a good antivir program like avira

The thing is I just re-activated my Windows 7 after changing from 32 bit to 64 bit and have been installing stuff all day. Can't be a coincidence surely?

I was googling for 'warranty scam' as he was talking trying to find references....

It's a scam, plain and simple.

Run a full anti-virus scan and if you get another call, leave the phone off the hook for a while to piss them off while you have a cup of coffee.

Coincidence? Possibly.

In cahoots with someone who has access to Microsoft's activation servers? Also possible.

I am very sure that its a coincidence. After all, most they can do EVEN if they know that you switched(0.00000001% chance) to 64 bit, they cant do anything

Formula for weird phone calls:

Hang up.

Microsoft will never call you under any circumstance. Except if you told them to do so via the Support Portal. Anyone calling out of the blue that say they are calling from Microsoft is a scam.