I need to add a new user, but with an old email

It's nice to see you here in the Community, drosas. Let me provide some information about adding users in QuickBooks Online.

In QuickBooks Online, you can assign specific roles and permissions to different users for collaboration and efficiency. If the user assigned a specific email address is no longer active, you have the option of removing that user to open the chance for the email address to be used for a different user.

Here's how to delete a user:

1. Go to the gear icon.
2. Select Manage users.
3. Click the ellipsis icon on the user you want to delete, then press Delete.
4. Hit Delete user from the pop-up window to confirm.

However, if the user is still active, then you'll need to utilize a different email address to assign to the new user. You can use this article for guidance in adding, managing, or deleting user profiles in QuickBooks Online: Add and manage users in QuickBooks Online.

For future reference, here's an article about adding your accountant to your QuickBooks Online company for collaboration: Add accountant users in QuickBooks Online.

If you need further assistance in adding a new user or managing your team in QuickBooks, please feel free to use the comment section below. I'll be around to help you out, drosas.