I can set most attributes for a new AD user with the New-ADUser cmdlet including c which takes the -country parameter. However I have problems trying to set the co attribute in AD. i thought it would have been as simple as -co but it seems not so simple.
There may not be a parameter to New-ADUser that sets that attribute directly, but it does have a fallback option that allows you to set any LDAP attribute that you need: -OtherAttributes. This parameter takes a hashtable of ldap attribute names to values: