How to update the Max Memory at SQL Server?

From the command prompt start sqlCmd using the Dedicated Administrator Connection (DAC). :

net start MSSQLServer /mSQLCMD /f

C:>sqlcmd -S ServerName -U sa -P –A

Once you are connected, execute the following to set the memory to 4 GB, it should be enough to allow you to reconnect using the Management Studio tool.

sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'max server memory', 4096;
GO
RECONFIGURE;
GO

Issues can be fixed by above process:
Sqlcmd: Error: Microsoft ODBC Driver 13 for SQL Server : Named Pipes Provider: Could not open a connection to SQL Server [2]. .

There is insufficient system memory to run this query.

Accidentally turned down SQL memory too low to log in, how do I fix?