I'm using Windows Messenger 4.7 and whenever I try to transfer a file larger than 1mb or so it transfers 99.9% then I get the following error. Anything small goes through just fine. I am on comcast cable. Any suggestions or should i actually contact the cable company? ----- We could not send this file because the connection is blocked. Please contact your network administrator or Internet service provider; they may be able to enable file transfers.