Exchange calendar not displayed

Hello community,

I' currently using 'El Captian' on my MAC and my calendar app refuses to connect to our companies exchange server.

Mail and contacts work fine, as other claedars (e.g. Google) do.

I get not response at all, not even an error message, when I add the exchange account to my calendar app.

I am using Version 8.0 (2092) of the calendar app.

Does anybody have an idea how to solve this?

Thanks

Sascha