See All Spam Filters

Cloudmark DesktopOne Pro

*Est. $20
February 2012
by ConsumerSearch
Cloudmark DesktopOne Pro

Best spam filter

  • Highly effective
  • Supports every email type
  • Low impact on system performance
  • Protects multiple email accounts
  • Competitive price
  • Windows only
  • More spam slips through when scanning mail in bulk
  • Annual fee

Critics across the board say they are happy with the Cloudmark DesktopOne Pro spam filter. The community-based filter hits accuracy rates of between 92 percent and 97 percent in various tests, with less than 1 percent of legitimate mail flagged as a false positive. That effectiveness is reduced when scanning large amounts of older emails at once, however -- hence the difference in reported accuracy rates. One expert found that DesktopOne Pro had issues identifying spam written in Russian or related to tax-time phishing schemes.

Unlike most other programs, Cloudmark DesktopOne Pro supports almost every type of email, including IMAP, POP3, webmail and mail on Microsoft Exchange servers. The software runs constantly as a standalone program. An option toolbar and spam folder are added to Microsoft-brand email readers as well as Mozilla Thunderbird; users of other email services can check junk mail and tweak configurations directly in the DesktopOne program. DesktopOne uses about 200 MB of RAM, reports, which shouldn't affect performance on most modern computers.

Experts report that installation is straightforward and should take less than five minutes. Adding contacts to the program's Smartlist is just as simple, especially if you're using an email client that supports the DesktopOne toolbar. The license (which must be renewed yearly) allows you to protect multiple accounts, as well. A free version offers the same spam-fighting capabilities, but only for a single account. Paid subscribers have access to technical support via email, but that's it.

Several publications deliver excellent reviews of Cloudmark DesktopOne Pro, which is a rarity in the spam filter field. and each deliver lengthy, testing-based critiques. PC World delivers a shorter, yet still informative and testing-based examination of its own. also chimes in, and finally, more than 20 users review the product at

Our Sources


Reviewer Neil J. Rubenking finds very little to dislike with Cloudmark DesktopOne Pro in this two page review. The program's effectiveness, ease of use and support for all email types leads to Rubenking giving it a perfect 5-star rating and an Editors' Choice award for best spam filter.

Review: Cloudmark DesktopOne Pro 1.2, Neil J. Rubenking, May 13, 2011


Steve Ragan finds Cloudmark DesktopOne slightly less effective than's Rubenking but still very effective overall. He also touches on the program's installation and impact on system performance, finding both more than acceptable. In the end, he says users should give the free Basic version a whirl before laying down cash for DesktopOne Pro.

Review: Review: Cloudmark DesktopOne, Steve Ragan, Nov. 29, 2010

3. PC World

Reviewer Preston Gralla doesn't give Cloudmark DesktopOne a numerical rating, but he sounds impressed in this text-only review. He says the software "does an excellent job of killing spam before you ever read it."

Review: Cloudmark DesktopOne for Outlook 2010, Preston Gralla, May 6, 2011


Cloudmark DesktopOne earns the number two slot on's list of the 10 best premium spam filters. Scores are assigned for a number of the program's components -- including protection, blocking/filtering, ompatibility and more -- but the extent of hands-on testing, if any, is not made clear.

Review: Cloudmark DesktopOne Pro Review, Editors of


User reviews at are a little more mixed than expert reviews. While most rate Cloudmark DesktopOne highly, a handful report issues with technical difficulties and spam detection. It's worth noting that these users are commenting on the free Basic version rather than the premium DesktopOne Pro.

Review: Cloudmark DesktopOne, Contributors to

Back to top