I have recently updated DSM on my Synology NAS to DSM 7, the version is showing as 7.0.41890. Have downloaded the server update package PlexMediaServer-1.24.0.4921-ce9f9dc95-aarch64_DSM6.spk
When I select the file to install it I get a message saying This package requires DSM7.0.0000 (update 0 or older.
Before blindly installing, carefully and thoroughly read the Release Info & Migration Instructions thread in its entirety, otherwise you will fail due to differences between DSM 6 & DSM 7.
If you have not done so, remove Plex Media Server from your NAS using the Synology Package Manager. Do not delete anything from the /Plex shared folder.
Then download the correct DSM 7 version of PMS for your NAS from plex.tv/download.
Edit: If you have a DS218, you want the ARMv8 version. If you have a DS218+, you want the Intel 64-bit version.
After reading the migration instructions, install PMS on your NAS.
The installation process will fail due to file/folder permissions that must be manually configured.
After setting file/folder permissions, you can proceed with a second installation that should succeed (Scenario 2, Step 4).
The Installation Issues thread may be of help if you run into problems during installation.