STMS: RFC communications error with system destinations

While using STMS  if  you experience below error,

RFC communications error with system/destination
%%ashost=ciSDS,sysnr=,lang=E,client=<nnn>,pcs=1,icce
RFC destination
%%ashost=ciSDS,sysnr=,lang=E,client=<nnn>,pcs=1,icce=1,cfit
=0x20 does not exist.

This can be caused by incorrect hostname in the communication tab of the TMS configuration. The

Target Host in the communication tab should match the Host name in SM51.

Alternatively it can be cause by missing System No. in the communication tab of the TMS configuration.

It's resolved with below solution:

Server name and Host name in SM51 are both either uppercase or both lowercase (they

cannot be mixed) and that the Host name in SM51 matches the Target Host in STMS.

If needed resolve the Host name in the communication tab manually via the domain controller but this

should not be required if SM51 has Server name and Host name correctly maintained.

If the issue is caused by missing System No. then please add the system number (again manually in the

communication tab via the domain controller) or else delete the system from STMS and

re-add it, keeping in mind if the system in question is the domain controller then you will need to activate the backup domain controller first.