Content-Transfer-Encoding: quoted-printable content-type: text/plain; charset="utf-8" X-RT-Original-Encoding: iso-8859-1 Content-Length: 594 Hello, I am testing Kerberos S4U2Proxy API (krb5_get_credentials_for_proxy()). Client is MIT Kerberos (version 5-1.21.2) test program, krb5-1.21.2/src/tests/s4u2proxy.c. Kerberos KDC is Active Directory (on Windows Server 2016). On making this API call, the client receives error "-1765328371, KDC can't fulfill requested option". Has this functionality been tested with Active Directory? Has it been tested with any other KDCs? Please share guidance about resolving this issue. I have reviewed the krb5-bugs archive and did not find a previous bug related to this issue. thanks, Rajbir