Hi, after Microsoft released their fix to CVE-2020-17049 a while back, I can't renew my tickets made against upgraded Windows servers. The details have apparently been reported to the kerberos mailing list earlier[0] but I'll show the symptoms: $ kinit Password for username@DOMAIN: $ klist -f Ticket cache: FILE:/tmp/krb5cc_1116501893 Default principal: username@DOMAIN Valid starting Expires Service principal 2021-02-01 23:57:41 2021-02-02 09:57:41 krbtgt/DOMAIN@DOMAIN renew until 2021-02-02 23:57:37, Flags: RIA $ kinit -R kinit: KDC can't fulfill requested option while renewing credentials If you need any further information, I can try to reproduce and help as I can (although James Ralston, the author of the aforementioned email, appears to know more about what he's talking about...) [0]: https://mailman.mit.edu/pipermail/kerberos/2020-November/022582.html -- Morten Minde Neergaard