No one knows what the actual problem is.. if someone did then a specific solution would be posted and that solution would work for everyone. This problem isn't restricted to Windows XP, as I also get it on my Windows 98, Windows ME and Windows Vista machines.

The reason there are a lot of various possible solutions posted here, is because no one has found a specific solution that works, most likely due to the generality of the error message. There is nothing in the message to indicate which piece of software caused the connection to abort, and even if it did, different people might be having this problem due to the usage of different software.

If you and/or your friend have no problems when running Vista, but do have problems when running Windows XP, then the solution for you/your friend is simple... use Vista not XP.