Server Version#:
Player Version#: Version 4.156.0
<If providing server logs please do NOT turn on verbose logging, only debug logging should be enabled>
I get the message: You do not have access to this server. Why Not?
I followed the steps regarding removing the registry entries, then logged back in but still the same error.
In Windows, open File Explorer. Paste the following path into its address bar: %LOCALAPPDATA%\Plex Media Server
Within that path, you should find a Logs directory. Right-click it and select Send to -> Compressed (zipped) folder. This will create a ZIP file named Logs.zip.
(This assumes you are using the default location for the Plex data folder.)