From this morning till now I test with this mail problems. I found it. Mea culpa that I need this long time to figured it out.
The only reasen to this problem was a wrong emailadress for one of my member. Goof!
Now I can say ElkArte works.
Im so sorry. I did not expect to wrong emailadress.
I asked myself:
Why is this not written in errorlog?
Answer:
The mailadress exists. A noninvolved get spamed by me. oh, my goodness....
NetFlag could kick himself.
It really does sadden me that you emanuele have unnecessary work with me.