Avira AntiVir is a completely free antivirus product. Is AntiVir as good as a paid program. No ... it's actually better than many! Read this review to find out what makes AntiVir the best free antivirus software currently available.
Overview
Avira offers AntiVir Personal - a limited edition of the Best Antivirus of 2008 – Avira AntiVir Premium to home user completely free of charge. Version 9 of AntiVir was released two months ago with new features and system requirements.
| System Requirements and Installation | Rating  |
AntiVir 9 can be installed on Windows 7, Vista, XP and 2000. Previous editions of Windows cannot take advantage of AntiVir 9. Existing users of AntiVir v8 can enjoy the upgrade without manually removing the existing program (but it’s best to remove older version prior installing a new one!) because the installer of AntiVir 9 will remove the older version. A reboot is required to replace the old files.
Installing AntiVir 9 as fresh install (new program installation instead of upgrade from older version) is an easy process and does not require a reboot. The program can be use and configure as soon as you finished with the installation.
AntiVir’s installer includes a simple Configuration Wizard to help you in configuring the program:
- Detection Level of its AHeaD Heuristics - for best detection rate, choose the highest level
- Extended Threat Categories – an option to choose which type of threats you would like AntiVir to detect. The default is detection on spyware, adware, backdoor client, dialer, double-extension files and phishing. Selecting all type of threat categories will give you protection against APPL which is protection against applications from suspicious sources, games (e-mail games or PC games that are not allowed at work), and annoying jokes for PCs, privacy risk programs and from unusual runtime compression.
- AntiVir’s Guard Startup Mode – there are two available modes for the on-access protection module by AntiVir: Normal or Secure Start. Normal mode is the default selection but it’s best to choose the Secure Start to enjoy the early load protection by AntiVir. Quite helpful if you want to prevent and remove malware before it will become active during Windows Startup.
- System Scan – like most antivirus program, AntiVir’s configuration wizard will offer to perform a system scan on active processes and startup and also to critical areas in Windows. I suggest to not to use this option and manually run a system after you finished updating the detection signature of AntiVir. Running a scan using old definitions might help only to detect old malware and as you know already, old signatures do not contain fixes for false positive detections.
| Features and Options | Rating  |
AntiVir 9 will now protect you against spyware and adware, which the older version of AntiVir does not. The new version also provides support for Netbooks and multi-processor machines. The key features of AntiVir 9 are as follows:
- Real-time protection against malware, Trojans, worms, virus, dialers, rootkit, spyware and adware.
- On-demand scan and Quick removal of detected malware
- Early Load Protection
- Quarantine and online submission of samples
- Scheduled Tasks to update and scanning
- Anti-Phishing
With AntiVir 9 you have the options to scan a single file, folder and drive. You can also add items in exclusion manager.
Tip: The default settings of AntiVir are good but it’s best to change the default settings to scan all files. Most antivirus is configured to scan only some file extensions and files that are known to infect critical system area. To get the best protection by antivirus program, always configure the settings to the maximum protection available.
| Performance and Updating | Rating |
Avira is offering free detection and program updates and it’s done automatically within the program or as per schedule. You have an option to manually install definitions update too in case you have more than PCs to install definitions update. Avira is considered as nagware because it will display a pop-up window when updating the program.
If you are using Windows Vista, the User Account Control (UAC) is not triggered when opening, configuring or updating AntiVir. The only time the UAC in Vista is displayed is during the installation and when manually updating the definitions 
(instead of using the built-in updater).
AntiVir 9 will use around 80MB (Commit Memory) on Vista which is higher if you will compare to its virtual memory usage on XP which is 58MB. When running a full system scan using the default scanner priority level, AntiVir will use more than 100MB of memory. It only took 38 minutes to finish a full scanning of the Vista system.