SSL certificate not trusted (ICM_HTTP_SSL_PEER_CERT_UNTRUSTED)

What causes this issue?

The SSL certificate for the server is not known as trusted in the PSE
file.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

If the SSL certificate for the server is to be made trusted, it must be
included in the list of trusted certificates in the PSE file. This can
be done by executing transaction STRUST.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.