Migrates users from a specified OU in Active Directory with Windows Claims identities to ACS identities

MigrateUsersToACS.ps1

asnp Microsoft.SharePoint.Powershell -EA 0 
Import-Module ActiveDirectory

$web = "https://www.contoso.com"
$windowsClaimPrefix = "i:0#.w|"
$acsClaimPrefix = "i:0e.t|acsidentifier|"
$domainPrefix = "contoso\"
$containerOU = "OU=Users,DC=contoso,DC=com"

Get-SPUser -Web $web -Limit All | 
ForEach-Object { 
    if ($_.UserLogin.ToString().Contains($windowsClaimPrefix)) { 
        $currentSPLogin = $_.UserLogin.ToString().Replace($windowsClaimPrefix,"").Replace($domainPrefix,"")
        #$mail = "*$($currentSPLogin)*"
        if ($_.Email.Length -gt 0) {
            $user = Get-ADUser -Filter { mail -eq $_.Email } -SearchBase $containerOU
            if ($user) {  
                $newUserAlias = $acsClaimPrefix + $user.UserPrincipalName
                Write-Output "Login: $($_.UserLogin)/UPN: $($user.UserPrincipalName)/New Alias:$($newUserAlias)"
                $_ | Move-SPUser -NewAlias $newUserAlias -IgnoreSID -Confirm:$false
            }
        }
    }
}