Failed to create keytab file with  below error returned:
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ktpass /princ HTTP/spotfireserver.research.example.com@RESEARCH.EXAMPLE.COM  /ptype krb5_nt_principal /crypto aes128-sha1 /mapuser spotsvc  /out spotfire.keytab -kvno 0 /pass spotsvcpassword
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Targeting domain controller: research.example.com
Failed to set property 'userPrincipalName' to 'HTTP/spotfireserver.research.example.com@RESEARCH.EXAMPLE.COM' on Dn 'CN= spotsvc,CN=Users,DC=research,DC=example,DC=com': 0x13.

WARNING: Failed to set UPN HTTP/spotfireserver.research.example.com@RESEARCH.EXAMPLE.COM on CN=spotsvc,CN=Users,DC=research,DC=example,DC=com.
  kinits to 'HTTP/spotfireserver.research.example.com@RESEARCH.EXAMPLE.COM' will fail.
Successfully mapped HTTP/spotfireserver.research.example.com to spotsvc.
Password successfully set!

Failed to create Keytab file with error "Failed to set property 'userPrincipalName'"

• Check whether the UAC is enabled on the server which you run the command on, if yes, please have a try to take that same command and run it on the same server after disabling UAC and rebooting server, then see if the warning is gone.
• In addition, make sure that the account which is used to run the command is from a member of Domain Admins, Schema Admins, Enterprise Admins, and the built-in Administrators group.
• If the above doesn't work, check if there are duplicate accounts with the same UserPrincipalName. You can try running the ktpass command with the shortname e.g

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ktpass /princ HTTP/spotfireserver@RESEARCH.EXAMPLE.COM  /ptype krb5_nt_principal /crypto aes128-sha1 /mapuser spotsvc  /out spotfire.keytab -kvno 0 /pass spotsvcpassword
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