Contacts Verifier is an add-in for Microsoft Outlook 2000/XP/2003 designed to monitor validity of e-mail addresses in the contacts. It is able of checking your address-book throughout in a few minutes to notify you of the contacts that contain e-mail addresses, which are no longer valid. Add-in supports mail merge mode in Word and Outlook, Socks5 protocol, and NAT to work in LAN, fast multithread verifying, and has comfortable user interface.