I browsed through the documentation of Cisco and the forum and nobody seems to have the same problem:
When I run the DBLHelper tool on my Publisher it shows, that everything is ok with Subscriber, but in front of the publisher the icon is red.
I checked in the SQL Enterprise Manager and the only thing I could see, is that the "Expired subscription clean up" job failed.
I don't know whether this is the root cause of the red icon or something else.
Any help appreciated, I also attached the screenshot of the DBLHelper and the DBL-Trace.txt file.