A scenario where WCF services were hosted to get large amount of data from another ASMX Service. The WCF Service was timing out and wasn’t able to return the data, but when testing the same Web Service on the same Server using another ASMX Web Service, to surprise it was working perfectly. This was tried many times and the behaviour was quite consistent. WCF Service was failing or behaving inconsistently, where as the ASMX service on the same server was working perfectly. After investigating the settings further, it was discovered that the issue was with the NETWORK CARD settings on the server.
The issue was due to the network card on the server not being set to Full Duplex mode.
Make this change by setting the NIC to 100 MB Full as shown below: