OCI checkout to HOOK_URL results in 400 Session timed out in SAP GUI for HTML

[sean_jorden]

We are attempting to setup an OCI connection to an external vendor from ME51N using SAP GUI for HTML. We are on S/4 1909.

Our configuration is as follows under Materials Management -> Purchasing -> Environment Data -> Web Services: ID and Description

Everything seems to work OK, however when the supplier's catalog site submits back to our HOOK_URL after we checkout, then we get a "400 session expired" message.

The HOOK_URL that it is trying to post to is as follows (anonymized with XXX)

https://XXX.hec.XXX.ca/sap(cz1TSUQlM2FBTk9OJTNhdmhudHJzZDFjaV9TRDFfMDAlM2FTUGRLeVdLa0VVOWN4ZkVIdFppY...

Anyone have experience with this? Some notes seem to point to webgui service parameters. Our SICF webgui service parameters are as follows

~WEBGUI 1

~XSRFCHECK 1

~DISCONNECTONCLOSEWS 1

[nazarene_madriaga]

I am also interested what is the answer for this as I have similar issue atm..

Regards,

Naz