Login to Plex in Browser won't work, although username/passwd are correct

Plex Media Server
,
1

Server Version#:1.42.2.10156
Player Version#:

Hello,

I run the Plex Media Server on a Linux computer. I access the server from my Mac (Browser, App, Plexamp), from 2 AppleTVs, from my iPad. It works flawlessly.

Now I put monitor, mouse and keyboard to my Linux computer (where the PMS is running) and try to reach Plex in a browser..

When I try to log in, I get a message saying that my username or password is incorrect. I have checked my login details several times and they are correct. I can log in on my Mac and in Plexamp using exactly these details. I tried it on the Linux machine at
https://app.plex.tv/
http://127.0.0.1:32400/web/

I tried Firefox and Vivaldi (Chrome-based). It does not work.
Any idea what I can do?

Regards,
Peter

2

Use the “Forgot Password” link.
If that doesn’t help, contact https://www.plex.tv/contact/?option=billing-issues#p-contact