Scenario 4: Users get "No logon possible" messages
There's probably nothing worse than not being able to start your SAP system. Where's the problem? The operating system? The database server? Or perhaps it is time to dive into the dark corners of SAP to get some answers? This handy troubleshooting guide by veteran site expert Giovanni Davila will help you figure out what's going on.
- Work processes start but no logins are possible.
- Users get the login screen but the system does not log them in. Instead, they get this error: No logon possible (no hw ID received by mssg server).
- In the SAP MMC, the message server (msg_server.exe) shows status "stopped".
- The dev_ms file reports these errors:
[Thr 2548] *** ERROR => MsCommInit: NiBufListen(sapmsTST) (rc=NIESERV_UNKNOWN) [msxxserv.c 8163]
[Thr 2548] *** ERROR => MsSInit: MsSCommInit [msxxserv.c 1561]
[Thr 2548] *** ERROR => main: MsSInit [msxxserv.c 5023]
[Thr 2548] ***LOG Q02=> MsSHalt, MSStop (Msg Server 2900) [msxxserv.c 5078]
Problem Analysis
Work processes were able to start but the message server was not. The reason is because the "services" file is missing the SAP System Message Port entry. Example: SAPmsTST 3600/tcp
Solution
Edit the "services" file and add the entry. Then, re-start the instance. Make sure you specify the appropriate TCP port (e.g. 3600) for the message server.
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TROUBLESHOOTING SAP STARTUP PROBLEMS
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Home: Introduction
Scenario 1: Dispatcher does not start due to a port conflict
Scenario 2: Dispatcher dies due to a database connection problem
Scenario 3: SAP does not start at all: no message server and no dispatcher
Scenario 4: Users get 'No logon possible' messages when they attempt to log in
Scenario 5: The message server starts but the dispatcher doesn't
Scenario 6: Work processes die soon after they start
Review: Conclusion and more resources