Browsing the BAM Portal returns HTTP Error 503

Scenario

You install and configure BAM Portal on BizTalk Server 2013 R2; which succeeds. When you browse the BAM Portal, the following error occurs:

Service Unavailable

HTTP Error 503. The service is unavailable.

 

The Windows Application event log shows error:

The Module DLL 'C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\15\isapi\spnativerequestmodule.dll' could not be loaded due to a configuration problem. The current configuration only supports loading images built for a x86 processor architecture.

Resolution

https://bartwullems.blogspot.de/2013_08_01_archive.html