"managed by" attribute of computer object

Question

Hi all,
I am working on a script to manage the computer's attribute "managed-by" through power shell. I have found the command Set-ADComputer "AAECNBJ003403L" -ManagedBy "dn_path_of_user" which does not seem to be a solution in
my ad environment.
In our environment, all the client machines are in one domain (machine.domain.com) and users from different domains (user1.domain.com ; user2.domain.com) logon to these machines ( all domains in same forest ). when I provide the DN path of the users which
is "cn=user,dc=user1,dc=domain,dc=com" in the command Set-ADComputer "AAECNBJ003403L" -ManagedBy "dn_path_of_user" I get the error as follows 
 Identity info provided in the extended attribute: 'ManagedBy' could not be resolved. Reason: 'Cannot find an object with identity: 'cn=user,dc=user1,dc=domain,dc=com under: 'DC=machine,DC=domain,DC=com'.
SO it is searching for the user object in machine.domain.com where the object does not exist. Please tell me if I can specify a user domain name in the command.

Answer 1

I need to dig into my customer's environment to know why it works for them when they add the user of a different domain. Yes, we were in the process of domain migration which has been delayed due to some incompatible applications.
We have also been using a script which is taking the input from a csv file and updating the managed by attribute of the machine. In the script we are specifying the domain  "user.domain.com" and it works for us when we need to update the attribute
in bulk. But we also need the command for updating the attribute of the individual machine as per the end user request. Please see the script below if this can be taken into reference. 
 Import-CSV C:\Users\W9a0n3p9\Desktop\comp.csv |%{
#Specify the search criteria
$Computer = $_.Computername
$samname = $_.Username
$domain = "user.domain.com"
#Get a list of domains in the forest and grab the DN of the one matching the above parameter.
$forest = [System.DirectoryServices.ActiveDirectory.Forest]::GetCurrentForest()
$domain = $forest.Domains | ? {$_.Name -eq $domain}
$domainDN = $domain.GetDirectoryEntry().distinguishedName  
Write-Output  "Found the remote domain, the full LDAP distinguished name is $DomainDN"
#Create an LDAP searcher object and pass in the DN of the domain we wish to query
$Searcher = New-Object System.DirectoryServices.DirectorySearcher([ADSI]"LDAP://$domainDN")
#Pass in the ceriteria we are searching for.
#In this case we're looking for users with a particular SAM name.
$Searcher.filter = "(&(objectCategory=person)(objectClass=user)(sAMAccountName= $samname))"  
$results = $Searcher.Findall()
#Loop through the results
Foreach($result in $results){
    $User = $result.GetDirectoryEntry()
    $userDN =  $user.DistinguishedName
    Write-Output "Set the Owner for Computer $computer as $userDN"
    $A= Get-adcomputer $computer
    $A.managedby = "$userdn"
    Set-adcomputer -instance $A
Regards,
Maddy