error 10061 durinG SAP LOGIN

Hello, please help me on this problem.

I’m failing to login to SAP R/3 IDES. I’m getting the following message:

Partner not reached

Component NI (network interface)

Release 620

Version 36

Module ninti.c

Line 979

Method NiPConnect2

Return Code -10

System Call SO_ERROR

Error No 10061

Error Text WSAECONNREFUSED: connection refused

Counter 1

The loopback adapter is connected

Thanks