How can a locate which device is sending a TCP Window 0? I am working with a web developer in my company who is have problems with access to his web site from a network which we only control a small part of the path and other corporate divisions control the rest of the path. External access does not seem to have any issues.
Sounds like you need to capture the packet stream going to/from your server. Wireshark is a good tool for this, and it's free to download. Once you have the capture, start looking for the TCP zero window events. Once you find one, follow the transaction backwards to try to determine which end of the connection is causing/suffering the problem.