Script Download:FixDuplicateMailAddresses.ziphttp://gallery.technet.microsoft.com/scriptcenter/Fix-Duplicate-Email-525089e4
This script enables you to export mail-enabled objects with duplicated email addresses. After correcting the attributes for these groups, you can use this script to import them to your on-premises Active Directory.
You can find more All-In-One Script Framework script samples at http://aka.ms/onescriptingallery