Bulk Convert AD Groups to Global

Convert-ADGroupsToGlobal.ps1

# Get all the groups in the OU we're targeting
$groups = Get-ADGroup –Filter * -SearchBase “OU=File Shares,OU=Groups,DC=Contoso,DC=com”

# Recurse through each group
Foreach ($group in $groups) {
  # Make it universal
  $group | Set-ADGroup –GroupScope 2
  # Make it global
  $group | Set-ADGroup –GroupScope 1
}