Microsoft Security Essentials: great, simple and FREE security solution for Windows

1. System requirements:
- One of the following Operating Systems (OS): Windows XP SP3, Windows Vista SP1/SP2, Windows 7.
 + For Windows XP:
   > CPU: at least 500MHz.
   > RAM: at least 256MB.
 + For Windows Vista & Windows 7:
   > CPU: at least 1GHz.
   > RAM: at least 1GB.
- VGA display: at least 800x600.
- Hard disk space: 200MB.
- Internet connection to download updates & definitions in the installation.
- Internet browser: one of these two:
 + Internet Explorer: 6.0 or later.
 + Firefox: 2.0 or later.
(Note: MSE also supports Windows XP Mode for Windows 7.)

2. Download link: MSE
(wait 5s, then click 'SKIP AD'.)

3. Main features & benefits:

- Real-time protection.
- System scanning.
- System cleaning.
- Windows Firewall intergration.
- Dynamic signature service.
- Rootkit protection.
- Protection against real threats, not good software (sometimes there are false positives, but this rarely happens).

4. Summarized reviews:

 > Pros:

  + Free.

  + Nice look (good user interface-UI).

  + Not very resource-consuming.

  + Pretty effective.

 > Cons:

  + Slow scanning.

  + No special/new features (comparing to other products).
 > In short:
 Microsoft Security Essentials (MSE) is a great security solution for PCs running Windows. It has all the basic features of a commercial security suite, but comes with a low low price of FREE. Besides long scanning time, MSE is an excellent choice with high effectiveness.