After system copy or sometimes due to some error RFC didn’t work. when doing connection test in SM59. it shows an message:-
RFC ERROR WHEN SENDING LOGON DATA
Check this SAP note – 1532825
ST22 shows entries like CALL_FUNCTION_CONNECT_ERROR or CALL_FUNCTION_SIGNON_INCOMPL
Solution is to manually delete 2 entries from SECSTORE.
Go to TX secstore
You find 2 entries with red traffic light, delete this entries.
Then go to TX se37
Execute the function module RFC_PING
if the system displays an error, execute the function module again, the error message cannot appear a second time.
Now issue is resolved.
Check entries in SM59. it will work now.