Powershell to loop through .CSV to create Distribution List?

Question

I want to modify the below PowerShell cmdlet to create bulk DLs with its members and its aliases.

Using the two cmdlets below:

• https://learn.microsoft.com/en-us/powershell/module/exchange/new-distributiongroup?view=exchange-ps
• https://learn.microsoft.com/en-us/powershell/module/exchange/set-distributiongroup?view=exchange-ps

I've managed to create just one DL when executed with the snippets below:

$paramNewDistributionGroup = @{
   Name                             = $_.DisplayName
   Alias                            = $_.Alias
   PrimarySmtpAddress               = $_.PrimarySmtpAddress
   DisplayName                      = $_.DisplayName
   RequireSenderAuthenticationEnabled = $False
   Members                          = $_.Members
}

New-DistributionGroup @paramNewDistributionGroup

$paramSetDistributionGroup = @{
   Identity       = $_.Alias
   EmailAddresses = @{ Add = $_.SecondarySMTPAddress }
}

Set-DistributionGroup @paramSetDistributionGroup

How to modify the above script so it takes the .CSV file which looks like the below:

Using the suggested code from @mklement below, it throws an error due to the multi-value entries on the below columns:

SecondarySMTPAddress column:

Write-ErrorMessage : Cannot process argument transformation on parameter 'EmailAddresses'. Cannot convert value "System.Collections.Generic.Dictionary`2[System.String,System.Object]" to type "Microsoft.Exchange.Data.ProxyAddressCollection". Error: "The address 'Execs@domain.com; boss@domain.com ' is invalid: The address 'Execs@domain.com; boss@domain.com' isn't a valid Unified Messaging address, so a prefix must be specified."

Members column:

Write-ErrorMessage : Ex94914C|Microsoft.Exchange.Configuration.Tasks.ManagementObjectNotFoundException|Couldn't find object " Cella Cat; Maria Aya; Heni Amor; Dio O'meara". Please make sure that it was spelled correctly or specify a different object.

Answer 1

Assuming this is on-prem Exchange?

$DLs = Import-Csv -Path <filepath>
$DLS | % {
    $paramNewDistributionGroup = @{
       Name                             = $_.DisplayName
       Alias                            = $_.Alias
       PrimarySmtpAddress               = $_.PrimarySmtpAddress
       DisplayName                      = $_.DisplayName
       RequireSenderAuthenticationEnabled = $False
       Members                          = $_.Members
    }

    New-DistributionGroup @paramNewDistributionGroup

    $paramSetDistributionGroup = @{
       Identity       = $_.Alias
       EmailAddresses = @{ Add = $_.SecondarySMTPAddress }
    }

    Set-DistributionGroup @paramSetDistributionGroup
}

I'm also going to assume the members within your CSV file match one of these AD attributes:

• Name
• Alias
• Distinguished name (DN)
• Canonical DN
• Email address
• GUID