NetWorker: NMC database backup fails "Unable to execute pg_basebackup.exe in order to copy the database"

Errors in the policy action log:

108179:savepsm: Replicating database contents to C:\Program Files\EMC NetWorker\Management\nmcdb_stage\pgdata...
108180:savepsm: Unable to execute C:\Program Files\EMC NetWorker\Management\GST\postgres_latest\bin\pg_basebackup.exe in order to copy the database
108181:savepsm: See 'C:\Program Files\EMC NetWorker\Management\GST\logs\pg_basebackup.log' for details
108179:savepsm: Replicating database contents to C:\Program Files\EMC NetWorker\Management\nmcdb_stage\pgdata...
108180:savepsm: Unable to execute C:\Program Files\EMC NetWorker\Management\GST\postgres_latest\bin\pg_basebackup.exe in order to copy the database
108181:savepsm: See 'C:\Program Files\EMC NetWorker\Management\GST\logs\pg_basebackup.log' for details

Errors in the C:\Program Files\EMC NetWorker\Management\GST\logs\pg_basebackup.log:

pg_basebackup: incompatible server version 12.18
pg_basebackup: removing data directory "C:\Program Files\EMC NetWorker\Management\nmcdb_stage\pgdata"

NetWorker periodically upgrades the postgres version used by the NMC. On Windows servers, the postgres version is symbolically linked using postgres_latest.

Sometimes when the NMC software is upgraded Windows does not re-create the postgres_latest symbolic link that links to the new version of postgres installed.

The issue outlined in this article appears when the postgres_latest link exists, but links to the wrong postgres version folder.
If postgres_latest does not exist, the NMC service does not start: NetWorker GST crash after NMC upgrade with IM003: The specified driver could not be loaded due to system error.

The steps outlined in this article resolve either scenario.

1. Open an elevated prompt on the NMC server and ensure that the NMC services are stopped: net stop gstd
2. Validate the services have stopped: tasklist | findstr gst
3. Open Windows File Explorer on the NMC server.
4. Go to C:\Program Files\EMC NetWorker\Management\GST.
   NOTE: This is the default NMC installation folder. If you have installed the NMC in a nondefault location, use your install path.
5. Delete the link postgres_latest (if it exists).
6. Go in to C:\Program Files\EMC NetWorker\Management\GST\postgres folder and confirm the latest version folder shown
7. Open an elevated prompt on the NMC server and re-create the postgres_latest symbolic link for the latest postgres version installed.

mklink /D "C:\Program Files\EMC NetWorker\Management\GST\postgres_latest" "C:\Program Files\EMC NetWorker\Management\GST\postgres\#.#"

8. Start the NMC service: net start gstd
9. Monitor the C:\Program Files\EMC NetWorker\Management\GST\logs\gstd.raw for any errors:

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