SOMAX2 and the dreaded "launch URL. err = 1223"

Hi,
I try to make SOMAX2 work. I have Windows 11 and Max 8.6.0. I installed the SOMAX2 basic version. When starting, it throws

Max could not launch URL. err = 1223

As described in some posts, I downgraded Miraweb to 1.2.6. I also added the vcredist_x64 2013 dependency, as in one post.

I also used Max 9 with Windows 11, did not work either.

No luck. No SOMAX2

P.S: I tried now the same on an older machine with Windows 10 and it worked

Any ideas?

thx hs