When trying to register the managed database for the ArcGIS server 10.5 through ArcCatalog it appears successful and will validate, but in the logs I get error 7415 (Failed to update the data store connections file, Registration of database is incomplete, Please re-register database).
When I subsequently try to deploy a FeatureService through ArcMap it fails with error 001369 (failed to create service) after failign to get the server's server only enterprise database.
I have tried changing the permissions on the config-store folder to give full control to all, and have also tried changing to a fresh config-store folder.
I have tried restarting the server, and unlocking and restarting the publishing tools service.
For the connection to the enterprise geodatabase I have tried connecting with the sde user, the sa user, and the ./arcgis service account user.
This occured when I was trying to connect to a freshly created geodatabase (which I did while working a separate issue) - I have been able to register the database and deploy feature services on this machine before.
Any help would be greatly appreciated, thank you.