I have a client here that's have a very unusal problem. They can access and navitgate around the internet without any problems, but when they try to go through a form submission the resulting form post never goes through and they get a timeout error. Also, they have several computers setup on their local network and they all behave the same across different internet browsers, (IE, Netscape, FireFox).

We've tried checking their MTU settings, but it seems to be set to 1472 which is the same on my network. We've also gone down the usual route of clearing cookies/cache/rebooting/rebooting the router.

Has anyone seen anything like this before? What could be stripping out a form post? Does anyone have any suggestions?

Thanks,