Error:
===================================
Cannot connect to SQL-SERVER
===================================
Login failed for user 'sa'. (.Net SqlClient Data Provider)
Resolution:

1. Ensure that the ‘sa’ account is enabled: security > right click user sa > Properties > Status > Enabled > save
2. Enable SQL Server & Windows authentication: right click on the server > Security > select radio button next to ‘SQL and Windows Mode’ > restart SQL or the OS