In some of the Windows Server 2008 and 2008 R2 servers which were not patched correctly or not up to date in terms of windows update, you might have some problems accessing BizTalk360 web application when the site is launched. Typically you'll see exceptions saying "No Default Document", "Static Content" etc

The main reason is because correct handler mappings or not configured in IIS 70/7.5. There is a hot fix available from Microsoft to resolve this issue. You can obtain this from this link

In addition, the basic prerequisite to debugging this issue is to verify whether you have installed the right patch for your Windows Server. The 2008 Server Edition and 2008 R2 Server edition have two separate patches and you need to have the right one installed depending on your server version.

Stage 2

You may still experience some issues, typically the Windows Communication Foundation extension .svc is not registered correctly. You can rectify this by running the following command

Open Command Prompt as Administrator and navigate to the following folder

C:\Windows\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\

and, execute the following command

ServiceModelReg.exe -i

Stage 3

You may still experience issue with exception something like this 

System.TypeLoadException: Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly 'System.ServiceModel, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089'.

This typically happens when the sequence of steps not performed in order, example ASP.NET was configured first, then WCF registrations happened etc. You can solve this problem by re-registering ASP.NET. You can run the the following command. 

aspnet_regiis -iru