If you think there's any chance you'll re-use that device as a Plex Media Server further down the line, you may not want to remove that particular server from the list of devices recognized by your existing server or servers unless it's truly causing you problems.Take great care to remove the correct server, because once you remove it, the sync and share information associated with it is gone forever and you can't get that back.You'll need to do this same process on each Plex Media Server that you want to remove an old server's information from.Click 'Yes, I'm Sure.' The server will be removed from the list of devices recognized by your new Plex Media Server.Click 'Remove.' A smaller message appears in that window asking if you're certain you want to remove the selected server.

A Remove Server dialog box appears, informing you that all syncs and shares associated with the server you're getting ready to remove will be lost.

Click 'X' in the upper-right corner of the box associated with the old Plex Media Server you want to remove.

Use the serve name and operating system that server is running as validation points to ensure you're removing the right server. On the right side of each entry, you'll see the name you assigned to the server, the last time you accessed that server, and the build of the operating system on that machine. You'll see an icon associated with the operating system the server is running on to the left of each entry.

Click 'Server' to narrow the list of devices down to the list of recognized servers.

The window on the right side of the screen will change to display all of the devices that have ever accessed your Plex account that you haven't removed.

Click 'Devices' in the Settings screen.

The Settings screen is where you can configure remote access on your Plex Media Server, modify transcoder settings, add and remove channels on your account, configure network settings, and more.

Click 'Settings' beneath Manage on the left side of the screen.

If you see the name of an old server in that list, it's still known to your current server. You can validate that an old Plex Media Server is appearing on a new Plex Media Server by clicking the name of your current server in the upper left corner of the home screen.

Open Plex Media Server on the machine you want to remove the old server from.

Max Dalton Steps to Remove an Old Plex Media Server from Server List

Plex makes it easy to delete old servers.

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