Information:

Environment

AppMon: 5.6, 6.x

Symptoms

The UEM of Dyntrace 5.6, 6.x bandwidth calculation doesn’t work on IIS Server when the static content is disable,  the UEM signal url "/dynaTraceMonitor” doesn't  work well, and gets 404 error.

Solution

IIS Server considers anything with text/plain in the header as "static content". In order to installing the Static Content role service if it does not. Please go to IIS Server Control Panel -> Server Manager -> Roles-> Web Server (IIS) node from the left pane -> scroll to Role Services window -> see if the Static Content role service is installed.

Root Cause

since AppMon 5.6 the dynaTraceMonitor payload is sent in the POST body and therefore the JS agent must set the content-type header:
Content-Type: text/plain;charset=UTF-8
When the Static Content is disabled on the IIS Server, the post body with such content-type would be blocked out.