If you want an open-source anti-virus utility that lets you scan on demand instead of real-time, you may want to take a look at ClamWin, a utility based on the ClamAV scanning engine.

This lightweight application integrates with Explorer and even has a plugin for Outlook to scan email attachments. It does not offer real-time scanning, so it won’t be for everyone and should probably be used by more advanced users.

Installing ClamWin

Installation of ClamWin is easy and straight forward.  The only thing to verify is that the Microsoft Outlook component is checked if you are using Outlook.

You might want to include international help files if necessary, although there isn’t a whole lot of choice there.

Using ClamWin

The ClamWin user interface is simple and basic.  Unlike other utilities there is no flashy or fancy graphics, just select a drive and kick off the scan.


The ClamWin Preferences accessed from (Tools Preferences) is where the user controls how the utility operates.  In this example I am setting the frequency and time of day ClamWin checks for virus database updates.

To schedule a scan click on the Scheduled Scans tab where you will notice there is nothing set up by default. You’ll want to click the Add button on the right-hand side to create a new schedule.

The Scheduled Scan box opens and you can set the scan frequency (daily, workdays. weekly, or monthly), the time and which day of the week if you choose the weekly scan option.  Here you will also browse to the specific folder to scan and then create a description. 

ClamWin does integrate into Microsoft Outlook and when you launch Outlook you get a ClamWin splash screen as to verify it’s protecting. 

After a few launches you’ll probably find that screen annoying, but you can easily disable it in Email Scanning under preferences.

Updating the virus database can be done manually or scheduled as shown in the instructions above.


ClamWin is extremely light on system resources even during an active scan, unlike most anti-virus applications where you notice a lag in performance. You’ll barely even notice it.

ClamWin saves reports for both database updates and scan reports.  You can easily access the reports by selecting Tools Show Reports and select either report.


ClamWin is very light on system resources and does a great job, with plenty of settings available to tweak to your liking. There is a great reporting system and virus database updates are available sometimes multiple times a day.

If you are experienced and looking for a light weight and solid open source anti-virus utility you should check this out. We should note again that this isn’t a great choice for inexperienced users since there is no real-time scanning.

Download ClamWin Anti-Virus

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