Resolving the "The value 'xyzportal' can only contain alphanumeric characters. A hyphen may be used in the middle of the subdomain; but, not at the beginning or end" Error

Overview

When trying to add a sub-domain within the customized branding page, you get the following error message:

This error will occur if the word "portal" is used as part of the sub-domain and will be blocked for use.

To resolve the issue, do not use the word portal (e.g., TaxClientPortal.smartvault.com).

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