HCL Domino Ideas Portal
Welcome to the #dominoforever Product Ideas Forum! The place where you can submit product ideas and enhancement request. We encourage you to participate by voting on, commenting on, and creating new ideas. All new ideas will be evaluated by HCL Product Management & Engineering teams, and the next steps will be communicated. While not all submitted ideas will be executed upon, community feedback will play a key role in influencing which ideas are and when they will be implemented.
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I think the only way would be to create a small agent, that sets the user categories according to your standards, or modify the mail template accordingly.
There is no policy entry for this, but might be a useful extension for the mail policy settings. However, as users an create their own categories, remove existing ones etc. this could only be an initial value.