El respaldo de NetWorker SQL VDI NMM de la instancia en clúster falla. No se puede encontrar el proveedor.

Los respaldos de Microsoft SQL Server pueden fallar con (NMM) NetWorker Module para Microsoft cuando el cliente es una instancia de SQL Server en clúster.  

El error típico es
 

Cannot login to SQL Server --Provider cannot be found. It may not be properly installed.

Por ejemplo: 

(pid=30180,2/25/2020 11:13:48 AM) D:/views/nw/19.2/nsr/db_apps/bsmsql/nsrsqlado.cpp(2261): Exiting GetProviderError().
(pid=30180,2/25/2020 11:13:48 AM) COM Error
(pid=30180,2/25/2020 11:13:48 AM) Code = 800a0e7a
(pid=30180,2/25/2020 11:13:48 AM) Code meaning = Unknown error 0x800A0E7A
(pid=30180,2/25/2020 11:13:48 AM) Source = ADODB.Connection

(pid=30180,2/25/2020 11:13:48 AM) Description = Provider cannot be found. It may not be properly installed.

(pid=30180,2/25/2020 11:13:48 AM) D:/views/nw/19.2/nsr/db_apps/bsmsql/nsrsqlado.cpp(1100): Exiting adoOpenConnection(), Exception.
66212 2/25/2020 11:13:48 AM  Cannot login to SQL Server VirtualSQLServerName\Instance01.

Este problema puede ocurrir cuando se produce un problema durante la instalación de SQL Server que hace que el nativo de SQL no se registre correctamente.

Por ejemplo, en

La lista de programas muestra

Microsoft SQL Server Native Client 11.0 para SQL Server 2012 y 2014

Referencias: 

https://learn.microsoft.com/en-us/sql/relational-databases/native-client/applications/support-policies-for-sql-server-native-client?view=sql-server-ver15#support-lifecycle-exceptionNOTA: Esto solo se aplica a las versiones de SQL Server hasta SQL Server 2017.  
Las recomendaciones de SQL Server Native Client cambiaron en SQL Server 2019 y versiones posteriores.

STEP 1.  Check registry  

Open Powershell on SQL Server and run,

Get-Childitem  "hklm:\software\microsoft\microsoft sql server"

RESULT:  
If you do not see a Key called "SQLNCL11"  then there is an issue with SQL Native Client.


STEP 2.   Connect to SQL instance using OLE DB Driver 

Open Powershell on SQL Server and run, 
 
$conn = New-Object System.data.oledb.oledbconnection
$conn.ConnectionString = "Provider=SQLNCLI11.1;OLE DB Services = -2;Server=VirtualServer\Instancename ;Trusted_Connection=Yes;"

##  where you will please replace   -  VirtualServer\Instancename  --  with  Actual Cluster server name and Instance name   

$conn.open() 

RESULT:
When Open contains no errors  then continue to next step. 
When Open fails then this confirms that there is a problem with SQL Native Client. 

$conn
$conn.close() 

To resolve this issue,

Run Start, Control Panel, Programs and Features, Uninstall Programs, 
you will see a version of,

Microsoft SQL Server 2012 Native Client 

Action:   Right click and select Repair.