For many companies, off-the-shelf security software is the main defense against online threats. We set up a dummy laptop and visited sites known for doling out malware and viruses to see how the following programs performed.

Trend Micro Worry-Free Business Security
Trend Micro's software allows administrators to manage local desktop security online. The software blocked all but two (mostly harmless) sites, but it did not remove some malicious apps.
COST: $31 a year per user for two to 25 computers

Symantec Endpoint Protection Small Business Edition
This program warns administrators of new attacks via e-mail or text. It did not block as many sites and programs as the other software we tested did. (Symantec says its software is designed to avoid false positives.) It also used the most computer memory.
COST: $35 per user for five to 24 computers, plus update fees

McAfee SAAS Endpoint Protection
Our top pick, this program also has an online management tool. It did not flag harmful websites like the other software we tested. But it blocked threats the others missed, including a program that tricks people into giving out credit card details.
COST: $35 a year per user for up to 25 computers