Hi @Avyayah,
Are you using BACKUP command directly, or are you using some third-party software?
If you are using third-party, please make sure SQL VSS Writer is started.
To open the services through control panel, click Start, click Control Panel, double-click Administrative Tools, and then double-click Services. In the Services pane, double-click the SQL writer service and modify the "Startup Type" property to "Automatic".
Service should then be started by selecting the "Start" button under the "Service Status" property in the service property screen mentioned above.
Make sure the SQL Server can access this backup device location.
Regards,
Zoe Hui
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