Especially as no-one's reported any problems and the computer is working just fine?
I had one of these calls this morning from a man with a strong (Indian?) accent who told me that my computer was running too slowly and that if I switched it on he could fix it in about 25 minutes. I asked him who had reported a fault and he said something about Microsoft but he was very difficult to understand.. I told him I was too busy and he wants to call back later. I've got no intentions of letting him have anything to do with my computer but wanted to check that this is a scam.
He asked for me by name so it wasn't a wrong number.
Does anyone have any knowledge or experience of this?