Hello Robin,
thanks for your reply, but we managed the problem otherwise. Basically we had two causes for the problem.
The first was the different domain of the webdispatcher (Portal) (xx.mycompany.com) and the reverse proxy for the SRM-System (yy.mycompany.com). This produces an "access denied" in one of the SRM-JavaScripts for the IE. It is a main security feature. Solution was an reverse proxy before the webdispatcher (Portal) in the same domain yy.mycompany.com.
The second problem was the HTTP connection between reverse proxy (SRM) and webdispatcher (SRM). So the SRM createt a call with HTTP to the reverse proxy (SRM). But this port doesn't exist there. The reverse proxy (SRM) switch to HTTPS but cut the url path away. Solution was a change from HTTP to HTTPS.
This are the solutions for now. I will look at the document HTTPURLLOC demystified
that you mensioned (Thanks for that), if we could speed up.
Thanks for your help.
Regrads,
Thomas