Scenario: A Citrix Engineer needs to configure Citrix Receiver auto-discovery. The company has the following standard for all users. SMTP: [email protected] UPN: [email protected] URL…

AD.MyCompany.com is the UPN suffix, not the SMTP domain; Receiver auto-discovery uses the email domain for SRV lookups, so this domain would never be queried.

AD.MyCompany.com is the Active Directory UPN domain and is not the Citrix server endpoint, so it cannot serve as the srv host that clients connect to.

Citrix Receiver auto-discovery performs a DNS SRV lookup against the domain portion of the user's email (SMTP) address. Since the SMTP address is [email protected], the domain used for the SRV record is Mail.MyCompany.com, not the UPN domain.

Mail.MyCompany.com is correctly the domain portion but is wrong in the srv host position - it is the mail domain used for lookup, not the Citrix server address clients must reach.

The SRV host value must resolve to the Citrix Gateway or StoreFront server that clients will connect to. Citrix.MyCompany.com is the published Citrix URL, making it the correct srv host target for the record.