Username and password are unchanged and supplied from a password manager. Used the same app to login to player and on other devices, so that’s not the issue. But I cannot sign into the server via web. I have some maintenance to do and and getting frustrated. Been two weeks.
I get a screen that thanks me for logging in successfully, looks likes it’s going to redirect to the server and then shows me the error screen.
I am having the same problem. Tried to just hit the Sign-In button, tried new email and password, also tried to sign in with email, then indicate that I forgot my password, thereby getting the password reset via email, but this does not work either. It initially says that I am logged into the server, then it says “There was an error signing in”, and it forces me to start the sign in process all over again. Very frustrating. I am using the latest version of plexmediaserver_1.20.2.3343-c91f25744_amd64.deb for Netgear. Apparently this version was released yesterday, Septermber 23, 2020.