2938087 - Posting action for FWSD results in error - Internal server Error / Message cannot be processed in plugin mode

User click the 'Post' button in the Forwarding settlement document and you get the message "500 Internal Server error/ Message A V1 158 cannot be processed in plugin mode HTTPS" , however dump does not occur in the system. After refresh the Forwarding Settlement Document the Life-cycle status is remaining in 'Ready for Posting' and Confirmation status is 'Not Yet Posted'. Important to know that this KBA is only applicable for External integration scenraio i.e TM and ECC are different systems and TM is built in S/4 version.

SAP Transportation Management embedded in SAP S/4HANA  

 Forwarding settlement, FWSD, Post, Error, 500 Internal sever error , KBA , TM-FWS , Forwarding Settlement , Problem