High-speed software designed to remove dead email addresses from huge mailing lists with millions of addresses. Moreover, it is with this list size that the program's highest performance can be achieved.

Version: 3.1High Speed Verifier (HSV) is a high-speed software designed to check e-mail address for existence. HSV is capable of checking thousands of addresses per second.
License: Free To Try $40.00
Operating System: Windows
Homepage: www.emmalabs.com
Developed by:
It can easily deal with mailing lists containing tens millions of addresses; moreover, it is with this list size that the program's highest performance can be achieved.
HSV detects about 20-30% of invalid addresses in a mailing list, though theoretically it is possible to detect up to 60-70% using a software product.
This figure seems relatively small, but actually it might make 10% of a list. Besides, HSV provides for optimal checking mode in terms of time and data traffic.
More thorough checking (with which the rest 40% of dead emails could be detected) takes 10 times longer and requires 5 times greater traffic for each address, hence it's not that advisable with huge lists.
What's New
Version 3.1: 64 bit version. Updater
Version 3.0: Added 64 bit version
Version 1.36.100: Improved stability. Updated DNS server list.