JSI Tip 3317. The commercial at sign (@) can cause problems in a SAM account name or UPN suffix?

If you create a user whose SAM (Security Accounts Manager) account name contains the @, or you use a UPN (User Principal Name) suffix that contains the @, you may experience strange behavior.

Active Directory behaves as if there is an @ between the SAM account name and the UPN suffix. If you add an unexpected @, some Active Directory administration tools, and/or authentication will experience problems.

While Microsoft supports the @ in the SAM, and authentication protocols support it, it is too similar to the UPN syntax to be reliably used. Some tools or interfaces will invariably fail.

If you create [email protected] as the SAM account name, Jerry must logon using [email protected]@<DomainName>.

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