2476789 - ABAP AS could not connect to database: SQL Error 17809

The ABAP Application Server does not start and fails to connect to SQL Server:

C  (233) [08S01] [Microsoft][SQL Server Native Client 10.0]Shared Memory Provider: No process is on the other end of the pipe.

C native_db_err 233 severity 0 errclass set to DBSL_EC_RESTART
C sl_glob.dbsl_ca.errclass set to DBSL_EC_RESTART
C ERROR: -1 in function SQLConnectWithRetry (SQLConnectWithRetry) [line 2460]
C (233) [08S01] [Microsoft][SQL Server Native Client 10.0]Communication link failure
C ERROR: -1 in function SQLConnectWithRetry (SQLConnectWithRetry) [line 2460]
C (0) [08001] [Microsoft][SQL Server Native Client 10.0]A network-related or instance-specific error has occurred while establishing a connection to SQL Server. Server is not found or not accessible. Check if instance name is correct and if SQL Server is configured to allow remote connections. For more information see SQL Server Books Online.
C ERROR: -1 in function SQLConnectWithRetry (SQLConnectWithRetry) [line 2460]
C (233) [08S01] [Microsoft][SQL Server Native Client 10.0]Shared Memory Provider: No process is on the other end of the pipe.

Upon checking the ERRORLOG file you find the following entry:

2017-05-20 11:43:50.21 Logon       Error: 17809, Severity: 20, State: 3.
2017-05-20 11:43:50.21 Logon       Could not connect because the maximum number of '7' user connections has already been reached. The system administrator can use sp_configure to increase the maximum value. The connection has been closed. [CLIENT: <local machine>]

Remark: the number of user connections, the SQL Server Native Client/ODBC Driver as well the Client and the host to connect may vary depending on your installation scenario.

• SAP Systems based on SAP NetWeaver;
• Microsoft SQL Server 2008 and higher;

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