Hi Haig,

the mail workflow in Odoo can be very confusing - I'll try to answer your question as best I can.

I assume that your office@ourdomain is set up as a catchall address - this means that incoming mail communication in particular is handled via this address.

1. if Odoo receives a message directly via the office@ourdomain without already being assigned to a specific record in the system, Odoo blocks the mail because Odoo cannot do anything with it. Normally you should create one or more aliases (to be found in the technical settings under Aliases) to forward the mail communication within Odoo. This means that if a message is sent directly to the office@ourdomain and does not yet have a record, the alias determines what happens to the mail afterwards - for example, the creation of a support ticket or a lead.

2. normally Odoo uses the user-specific mail addresses of the users and sends on their behalf. However, you can use mail templates (to be found in the technical settings under Mail templates) and enter ‘office@ourdomain’ in the ‘From’ field in the template settings. If a template is used, it will always be sent via the office@ourdomain. If you now always want to have the specific sender as ‘Reply to’, you must use the dynamic content ‘{{user.email_formatted}}’ on the template. The reply address is then always set to the user.

Hopefully that helps!

Otherwise I would suggest consulting:  https://www.odoo.com/documentation/18.0/applications/general/companies/email_template.html?msockid=1e563114daaf66740564243ddb636701

Regards,
Chris Dominiak (Intero Technologies GmbH)