I still use Cinema4DR19 and it wont start on Win 11, so I downgraded my new computer to Win10/v.1909.
The tipps I found, was that it is based on a Firewall Issue and you can simply make a Firewall rule to prevent Cinema4d using the internet. That works, but this also prevents using plugins like X-Particles oder Octane from working. (you can switch rule on/off but that only helps a short time)
The tipp says that it appears from Win 10/ 20H1 and ongoing.
BUT – I checked my old Computer and everything runs fine on Win10 / 21H1 (build 19043.2006)
I tried to copy paste my complete folder, but this didn´t do the trick – dirty I know.
Is there anyone that can help me on this ? Or any hint on Network Diagnostic to check what to do ?