Exchange 2007 script problem

Question

If I comment the first line and uncomment the second the script runs as expected, or when it's run for one individual contact.  But when it's run against the entire OU it fails and returns the error at the bottom of the posting.  Any ideas?
$MC = get-mailcontact -organizationalunit "OU=myOU,DC=domain,DC=com" -resultsize Unlimited
#$MC = get-mailcontact "George"
ForEach($Contact in $MC) {
$TargetContactExternalAddress = $Contact.ExternalEmailAddress
$TargetContactExternalAddressString = [string]$TargetContactExternalAddress.AddressString
Set-mailcontact $Contact.Name -WindowsEmailAddress $TargetContactExternalAddressString
WARNING: Object domain.com/myOU/George has been corrupted and it is in an inconsistent state. The following validation errors have occurred
WARNING: Could not convert property WindowsEmailAddress to type SmtpAddress. "George" is not a valid SMTP address
WARNING: Object domain.com/myOU/Nick has been corrupted and it is in an inconsistent state. The following validation errors have occurred:
WARNING: Could not convert property WindowsEmailAddress to type SmtpAddress. "NicK" is not a valid SMTP address
ETC

Answer 1

Hi FromDun,
Agree with Tony, this issue occurred because the variable $TargetContactExternalAddressString haven't returned as a smtpaddress.
To handle the error, you can also try and catch to get the failed contacts:
$MC = get-mailcontact -organizationalunit "OU=myOU,DC=domain,DC=com" -resultsize Unlimited
#$MC = get-mailcontact "George"
ForEach($Contact in $MC) {
try{
$TargetContactExternalAddress = $Contact.ExternalEmailAddress
$TargetContactExternalAddressString = [string]$TargetContactExternalAddress.AddressString
Set-mailcontact $Contact.Name -WindowsEmailAddress $TargetContactExternalAddressString -ErrorAction stop}
catch{
Write-Host "$($contact.name) get error $($_.exception.message)"
If there is anything else regarding this issue, please feel free to post back.
Best Regards,
Anna Wang