Hi @story2022 • Thank you for reaching out.
The add "new guest user" option might be unavailable due to:
1) The "Guest invite restrictions" setting under Azure AD > User Settings > External users > Manage external collaboration settings is configured with either 3rd or 4th option, as highlighted below:
2) If it is set to 3rd option, make sure that any of the admin roles mentioned below are assigned to your user account.
- Guest Inviter
- User Administrator
- Global Administrator
If it is set to 4th option, you need to contact the global administrator of your tenant to change this setting.
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