Moon Reader demands for opds and then rejects it

[Hschwickart]

After Moonreader launched Version 9.0 i couldn't access Calibre Server any more. There was simple no reaction.
I created a new web library and than Moonreader moaned about the opds option. When I left it out, it requested it again and rejected it again.
A hint in Calibre Companion led on the path to Calibre saying that the Wifi access component and server may not have the same port. That solved some other issues, but not that of Moonreader. Finally closing down the Wifi option solved the problem with Moonreader also.
Part of that problem is that the apps are not tested properly. It may be complicated to find out the reason of the problems, but should not result in a misleading error message.