Error while trying to update database for sqlcachedependency.

I keep receiving the following messsage from the command prompt while trying to update database for sqlcachedependency.

What should I do? Where is the mistake? I'm following this post:

https://docs.microsoft.com/en-us/aspnet/web-forms/overview/data-access/caching-data/using-sql-cache-dependencies-cs

Copyright (C) Microsoft Corporation. All rights reserved.


Enabling the table for SQL cache dependency.

...............An error has happened.  Details of the exception:
A network-related or instance-specific error occurred while establishing a conne
ction to SQL Server. The server was not found or was not accessible. Verify that
 the instance name is correct and that SQL Server is configured to allow remote
connections. (provider: Named Pipes Provider, error: 40 - Could not open a conne
ction to SQL Server)

Unable to connect to the SQL database for cache dependency registration.