harryp
Well for starters, osTicket is an email-based system. Our system is built around emails. With this being said, you can configure a fake or non-working email and set it as the system default address. That way nothing is ever sent out as it's not a real/working email.
For Agents and Users however we use email addresses as unique identifiers. So unique email addresses are required for each Agent and User. Again, you can have them use fake/non-working emails to get around this requirement.
Cheers.