get-mailbox |% {$a = $_.emailaddresses; $b = $_.emailaddresses; foreach ($e in $a) {if ($e.tostring() -match "domän.com") {$b -= $e;}}$_ | set-mailbox -emailaddresses $b}
get-mailbox |% {$a = $_.emailaddresses; $b = $_.emailaddresses; foreach ($e in $a) {if ($e.tostring() -match "domän.com") {$b -= $e;}}$_ | set-mailbox -emailaddresses $b}