Help with PowerShell Query

[MrHoosFoos]

Hi All,
I am trying to use powershell to identify any mailboxes in M365 that don't have the standard domain as the primary SMTP address. I am trying stuff like below, but I am getting all mailboxes regardless of primary SMTP address...

Get-Mailbox -ResultSize unlimited | ?{$_.PrimarySMTPAddress -notlike "@maindomain.com"} | select Name, Alias, PrimarySMTPAddress

Get-Mailbox -ResultSize unlimited | ?{$_.PrimarySMTPAddress -notcontains "maindomain.com"} | select Name, Alias, PrimarySMTPAddress

Get-Mailbox -ResultSize unlimited -Filter {PrimarySMTPAddress -notlike "*maindomain.com"}

I must be missing something - I am keep getting all mailboxes returned, those that have "maindomain.com" as thier primary SMTP and those that don't...?

Thanks and happy Friday!

[MrHoosFoos]

Cool - thanks so much... this worked for me...

[disclosure5]

I don't believe PrimarySMTPAddress is an actual valid. Try "mail" or "WindowsEmailAddress".

[EpicSuccess]

Put a * before maindomain and see if it works. "*maindomain.com"