Async socket send problem?

[Benny_Lava]

Hi, I have a Async socket receiving app and a sending app, the receiving app works great. The problem is when i'm sending something with the sending app ( begin connect -> endConnect, BeginSend - >EndSend) The begin send callback which on the first line does: private sub beginSendCallback(byval ar as iAsyncResult) socket.endsend(ar) end sub ' This callback method is called in a matter of seconds, but the 'file has about 3-4 MB, and the sending isn't near to completion, I have a list of IP addresses in which to send the file, but because the sending to the first IP address isn't finished, although the callback method is called it moves on, and of course creates an error later in the program... So how do I stop the callback method from calling itself until the file transfer is complete, or how to somehow know when the file is completely transferred. Thank you!