Why do I have to log in?

Randomly, when I access plex at url 192.168.1…/web/index.htl I have to sign in, and then select my preferences. Does anyone know why this happens? And how to get it to stop? Using Synology NAS.

Login is always required to access a Plex server.

That being said, your issue appears to be a different one:
For some reason, your web browser appears to have lost all data about Plex.
This is commonly caused by either

  • the web browser itself, if it has an option to automatically delete all cookies and website data after it is closed
  • the user, who clears the cookie storage of the web browser intentionally
  • certain 3rd-party software aiming to improve privacy or claiming to speed up the computer by “removing garbage”. These usually do the same (among other things) as the above options.

Create exceptons in your browser and in 3rd-party tools to preserve cookies and website data of plex.tv.
Never delete ALL cookies in your web browser manually.