DSM 6 → DSM 7 Migration Process

NOTE: Use the Plex package from Media Server Downloads | Plex Media Server for Windows, Mac, Linux, FreeBSD and More 824 ONLY. Package Center is no longer compatible with Official Release DSM 7.0-41890 and above.

Use the following steps then continue below as is appropriate for your configuration.

  1. Uninstall the DSM 6 Plex app
  2. Control Panel – Shared Folders –
  • Verify the Plex share is spelled “Plex”.
  • If not – Rename it to “Plex-temp” and then back to “Plex” (How DSM does it) if necessary
  • Certain older systems were created with the name “PLEX”.
  1. Control Panel – Security – Set the idle timer to 65536 minutes.
  • Restart DSM to make effective.
  1. Now upgrade to DSM 7
  • Setting the idle timeout ensures DSM will not disconnect you during the migration process. You can restore to the default value after migration completes.

Screenshot from 2021-08-08 00-02-00

  1. Restart DSM 7 one more time before starting installation. (yes, it does make a difference)
  2. Now begin installation.

Special consideration.

Due to a change which became effective in PMS, once upgrading to PMS or above, lower versions of PMS for DSM 7 cannot be used.

  • The storage locations changed and are not backward compatible.
  • Sorry for any inconvenience this might cause.
  • We are working with Synology to get them to update the version available in Package Center to avoid future problems.

DO NOT SHUTDOWN OR RESTART during this migration process.

Begin Plex installation here

  1. DSM 7 required we change both the service username (Plex → PlexMediaServer) and the shared folder (Plex → PlexMediaServer).
  2. The installer will expect the new username “PlexMediaServer” to already exist and have Full Control of the Plex share. It will not so the first attempt to install will fail.
    This is expected.
  1. We will now give PlexMediaServer Full Control of the “Plex” shared folder.
  • File Station – Right-click “Plex” → Properties → Permission tab.
  • Click Create.
  • In the username scroll selector, scroll down and find PlexMediaServer.
  • Check the box to select it.
  • Also click all three categories of permissions (Administration, Read, Write)
  • Click “Done” to close the Permission Editor.
  • Check the box to “Apply to this folder, sub-folders and files”.
  • Click SAVE. Observe DSM applying the permission changes to the Plex share.
  1. When complete, close the windows to return the installer page
  2. Click DONE to start the installation.
  • If there are no errors, Observe the installer processing your files and “Installing”.
  • If the installer finds something it does not like, follow the instructions given in the popup window and try again.

NOTE: The amount of time required to complete “Installing” will be dependent on the amount of media indexed.

  • The installer will require approx 3 minutes for each 1000 items you have indexed.
  • The amount of time will increase if you’re installing PlexMediaServer on a different volume than it was installed on with DSM 6. This is because it must copy the files from one drive to another.


  • DO NOT restart the Synology until after migration is complete. You will end up with a broken installation which might not be recoverable.
  • DO NOT attempt to interrupt the installation unless you fully intend to start from scratch with your Plex installation. Interrupting will result in data loss.


The installer keeps its status in the log file Plex/Migration.log

This is a sample of what you will find in Migration.log

Plex Media Server migration to DSM 7 started:  Sat Oct 30 15:26:16 EDT 2021
=== Sat Oct 30 15:26:16 EDT 2021 === Start: Change ownership
=== Sat Oct 30 15:29:45 EDT 2021 === Completed: Change ownership
=== Sat Oct 30 15:29:45 EDT 2021 === Start: Convert symbolic links
=== Sat Oct 30 15:34:41 EDT 2021 === Completed:  Convert symbolic links
=== Sat Oct 30 15:34:41 EDT 2021 === Start: Migrate Plex Media Server
=== Sat Oct 30 15:34:41 EDT 2021 === Completed:  Migrate Plex Media Server
=== Sat Oct 30 15:34:41 EDT 2021 === Completed:  Migrate Plex Media Server
=== Sat Oct 30 15:34:41 EDT 2021 === Start: Clean /volume1/Plex
=== Sat Oct 30 15:34:41 EDT 2021 === Completed: Clean /volume1/Plex

When Complete

When installation and migration is complete, you will see a final popup similar to: