TNS-12518: TNS:listener could not hand off client connection TNS-12560 TNS-00530 32-bit Windows Error: 2: No such file or directory

Event: When more users are making connection, Connection is breaking

Error:

TNS-12518: TNS:listener could not hand off client connection

TNS-12560: TNS:protocol adapter error

TNS-00530: Protocol adapter error

32-bit Windows Error: 2: No such file or directory

RCA:

1) check listener.log size if in GBs then stop listener services and rename it and start listener services

2) check sga size of all database on that server and compare with server RAM

3) check virtual memory and set it to recommended by windows.

4) Restart server to apply virtual memory settings.