It’s easy to wonder why your antivirus suite needs exceptions and whether they’re something you should set up. Excluding certain files from a virus scan might surely mean viruses can hide in your system, but allowing your antivirus to scan every file on your system is likely to lead to a terrible false flag sooner or later.
Why do antiviruses have scanning exclusions—and what are their pros and cons?
What Are Antivirus Exclusions?
Antivirus exclusions are a type of rule you may set in antivirus applications such as Windows Defender that prevents them from scanning particular files or directories. In many cases, exclusions are helpful. Certain software vendors recommend that exclusions are set for their programs because it preventsantivirus programs raising false flags.
That’s not to say that antivirus exclusions are without their drawbacks, however. Whenever an exclusion is set for a particular directory or file, your antivirus program will be unable to monitor it—and this presents an issue if a virus does take advantage of those files. You should remain mindful of any exclusions you set in your antivirus for this reason.
Why Are Antivirus Exclusions Important?
It’s important to set exceptions in your antivirus because this will protect the software and files you have on your computer from unintentional damage. Some legitimate applications will resemble malware when examined by antivirus programs because they use many of the same techniques to operate.
In some cases, setting antivirus exclusions can also lead to improved performance. This will be the case if your antivirus scans files synchronously as they are accessed and executed: the application you’re running will need to wait for the antivirus to finish accessing the file before it can do so itself. The microsecond delay following each attempt at access could eventually add up to minutes or hours of lost performance.
You don’t have to set an exception for every program you use. In fact, settings you may exclude certain directories or files from synchronous scanning are likely much better in these cases than total exceptions. It’s important to consider each potential exception thoroughly so that you can find the best balance between security and usability.
What Are the Pros of Antivirus Exclusions?
The primary advantage of setting antivirus exclusions is that you’re able to improve the performance of applications (if you use synchronous scanning) and you can improve the stability of system files.
Improved Performance
Synchronous scanning is an excellent feature. It’s effective at preventing malware from executing because it scans every file accessed and run by your system before they have the potential to do any harm. This synchronous scanning can slow down applications, however.
Setting a custom exception for a particular application is a great way to boost its performance. If you don’t use synchronous scanning, though, it’s worth noting thatyour antivirus is unlikely to affect your PC’s performance.
Heightened Stability
Custom antivirus exclusions can also help stabilize the operating system and applications you have installed by preventing your antivirus application from breaking or quarantining the wrong files. Unfortunately, antivirus programs are prone to raising false flags once in a while—and setting exclusions for directories and files you anticipate your antivirus flagging is a great way to improve the usability of your system.
What Are the Cons of Antivirus Exclusions?
Obviously, the habit of setting antivirus exclusions isn’t without its cons. You will have to contend with a reduction in overall security if you decide to set exceptions for antivirus scans.
Reduced Security
The main issue with antivirus exceptions is, naturally, that they prevent your antivirus program from scanning them. If malware infects files or directories that you’ve excluded from scanning, you won’t receive any notification regarding it—and this can set the stage for a serious infection to take place. If you must set exclusions, you should useMicrosoft’s guide to exceptionsand follow their recommendations closely.
Potential Errors
While the risk of errors isn’t as prominent as the risk of malware, it is also something you’ll have to contend with after setting exceptions. Many custom exceptions can break features like file IOCs and certificate IOCs that are directly dependent on your antivirus program.
You should avoid setting exclusions recklessly and only create them when a situation leaves you with no other alternative. Otherwise, you may run into something like theWindows Security unexpected error—and generally speaking, these exception-induced errors aren’t easy or fun to reverse.
Configure Your Antivirus Correctly
Antivirus exceptions need to be applied carefully. If you misuse and over-apply exceptions, you may put your system at risk of a breach. And if you avoid using exceptions altogether, you’re likely to hit a snag sooner or later when your antivirus breaks an important application. You should read about the different settings in your antivirus so that you can find the best possible configuration to balance usability and security.
