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The rise in popularity of free online scanning services urged developers to make web scanners as user-friendly as possible. In fact, each such scanner is very easy to use because all it requires is just several mouse clicks.
The marketing war is behind proprietary inventions and proprietary algorithms; Online virus scanning is typically powered by the same engine as a standalone antivirus product. Each company tries to implement some peculiar characteristic to differentiate its product from the competitors. Therefore, figures such as the detection rate and scan time, the ability to remove found infections, the option to scan for spyware and rootkits, the smallest size of the signature database, the progress window easy-to-use analytics greatly increase the likelihood of becoming popular with end users.
However, we must always remember that online virus scanning is very different from any desktop version of the product. It certainly has its advantages, but there are also negative points. The pros and cons of online scanning services are listed below.
So what can we consider to be the strengths of almost all online antivirus?
1. They are all free.
2. Every time you start such a scanner, you can be sure that it will use the latest virus threat database compiled by the vendor’s security labs.
3. Wide selection of virus scanners. While you often can’t install two or more different antivirus solutions on one Windows desktop, when it comes to online scanning, you can choose the one you like best, with no limits here. So you can switch between multiple scanners when you need to.
4. Sometimes it happens that the installed antivirus software is damaged by malware, so you can’t use the standalone product. You cannot reinstall or repair it because clever virus writers foresee such actions on your part and also corrupt Windows setup routine. In such a case, online virus scanning is often not just the easiest, but the only escape you have left.
5. No additional files are placed in the Windows registry or system folders, so system settings are not changed.
6. Online scanning is a good way to test PC security and check your protection.
But there are serious drawbacks typical of online scanners, and you should be aware of them.
1. Of course, it all starts with a stable internet connection. Without it, you cannot use the online services.
2. Proactive defense is a feature of standalone PC security products only. Online virus scanning cannot serve as a security shield. It simply finds the threats and removes them, if possible. When the scan is finished, there is no guarantee that your PC will not get infected the next minute.
3. Sometimes a virus living inside the PC can prevent the online scanner from downloading its database files to the hard drive.
4. The types of malware detected by online scanning are typically much fewer than those found by a full-featured stand-alone antivirus product.
5. Most online scanners require Internet Explorer with ActiveX enabled.
With all that said, I highly recommend using an online scanner from time to time, just to be on the safe side. You can complement the installed antivirus solution and test the security shield. It is free, after all.