Request format is unrecognized

[ Issue ]

After .Net web service deployment, the web service returns "System.InvalidOperationException Request format is unrecognized" (System.InvalidOperationException 無法辨認要求格式) whatever browse to [xxx].asmx or [xxx].asmx?wsdl .

[ Solution ]

1. Check IIS protocols in management console
     Make sure HttpSoap, HttpGet, HttpPost are list

2. Investigate web.config in [IIS Root]/web.config, e.q. c:\inetpub\wwwroot\web.config
    Check if there any "<clear />" in system.web->webService->protocols

3. Manual remove "<clear />" from web.config then apply the change