BackUp Database to NAS

When specifying the path to the Network attached Storage as a database backup storage in SQL Server Management, make sure the path starts with double forward slashes. If the path starts with for example (Z://) SQL server management doesn't accept an attached drive as a storage back up. 


Solution:
Open file explorer, find your storage (choose the computer icon under Network computers) and get the path, past the path into SQL server management backup path. 
e.g: (\\MYSTORAGE-89765\Public\BackUps\nameOfFileDatabaseTobackup)