Computer viruses have caused many problems for computer users since the first operating systems. It is not surprising, because some types of threats can completely disable both software and hardware components of a computer, laptop or mobile device. With operating systems and programs installed in their environment, there seems to be no ambiguity, but many may object to how the hardware used fits here? Everything is simple. Suffice it to recall the threats that at one time affected computer monitors, focusing the supply of maximum energy to one area or point of the screen, due to which the screens instantly burned out and could not be repaired. But that's all, hopefully, in the past.
However, modern viruses have changed quite a lot and are also capable of doing a lot - even stealing confidential user information. So let's see how to check a laptop, a stationary computer terminal or a mobile device for viruses usingthis is the tools available on the market for such software. But first, it is worth deciding on the main symptoms that may signal that a virus has settled in the system.
When should I scan my laptop for viruses?
In general, installing an antivirus is the very first and necessary step after installing the operating system. Everyone knows this. However, it should be noted that not all such programs are able to withstand the impact of modern threats. Some of them can disguise themselves as official software so well or infect files in such a way that it is not always possible to detect the presence of their executable code. Sometimes, however, users themselves ignore warnings, for example, when clicking on an unsafe link in a web browser. But the Internet today can be called one of the most extensive hotbeds of all kinds of threats.
Identifying the main types of viruses in the system is sometimes quite simple. As a result of their exposure, the following symptoms may occur:
- decrease in performance due to excessive loads on the processor or RAM;
- incorrect operation of the operating system;
- inability to run installed programs or call some system functions;
- frequent hard drive errors;
- blue screens of death;
- activation of unknown or dubious processes observed in the Task Manager,
- constantly pop-up ads, substitution of search engines and start pages in browsers, as well as redirects to resourcesquestionable content;
- inability to access the internet or network environment;
- spontaneous shutdown or restart of a computer device;
- permanent reset of system settings and parameters;
- Spontaneous installation of programs or appearance of unauthorized downloads, etc.
Of course, it is possible and necessary to combat such manifestations of viral activity, but in most cases only advertising threats belonging to the Hijackers, Malware and Adware classes can be manually neutralized.
Of course, some of the symptoms presented in the list may also occur in case of failures in the operation of the operating system itself or installed equipment, but such situations are much more typical for viruses.
Basic methods and means of verification
Speaking of how to check a laptop for viruses, you first need to decide which method or software will be used for such a check. It is the choice of the appropriate security software that largely determines the effectiveness of scanning, removing a threat, or disinfecting infected objects. Typically, these applications are used to perform verification:
- In-house threat prevention or scheduled scans;
- portable utilities of all kinds that do not require installation on an infected hard drive;
- programs with built-in loaders, launched before the start of the operating system;
- specializednarrowly focused utilities for detecting threats of a certain type.
As already mentioned, both visual threat detection tools and manual virus removal can be used. How to check if there are viruses on a laptop in these ways?

The easiest is to identify suspicious processes in the "Task Manager" with process names consisting of a meaningless set of characters, determine the location of the file responsible for the process on the hard drive, terminate the active virus process and delete the corresponding files and directories (if Maybe). But this helps very rarely, since viruses can disguise themselves as system processes (for example, under the svchost.exe process or other services), and it is not always possible to determine that this is a virus. Therefore, it is better to give preference to special software, the developers of which can be found quite a lot today.
Using regular antiviruses
Established antiviruses are good because for the most part they prevent the penetration of threats of any type, from any space and from any medium. Most of these software products have built-in protection against infection. But even they do not always cope with the duties assigned to them.

However, if nothing else is available, you can first run a standard scan (often referred to as S. M. A. R. T.) or an in-depth scan withindependent choice of objects to be checked. As for choosing a scanner, it is better to initially install only official versions (preferably paid or shareware). From free software, it is best to give preference to the products of Kaspersky Lab, Doctor Web, Panda Cloud antivirus, etc. But it is better not to use Avast, which is touted by everyone, since there are enough complaints about its work.
Some shareware antiviruses like some ESET packages need to be activated every thirty days. This is somewhat inconvenient, but keys and licenses can always be found freely available on the Internet. It goes without saying that for most of these programs, instructions are included in the help system. How to check a laptop for viruses in a practical way? Just set the desired scan type, select the desired action when a threat is detected and wait for the results.
Portable utilities
The advantage of portable applications is that they do not need to be installed on a hard drive, but can be launched even from removable media in the form of ordinary flash drives, memory cards, optical or external USB HDDs.

You can check your laptop for viruses using these programs in the same way as it is done when using regular scanners. The only difference is that when you run any such utility, you must first update the anti-virus database.
How to check before system boots?
Some viruses can infect a system enoughdeep, settling even in RAM and constantly keeping its non-pageable modules in it, which may affect the failure of the operating system to load. Among the boot programs written to external devices, the most preferred are utilities with the general name Rescue Disk.

The most powerful, according to the vast majority of experts, is considered such a utility from Kaspersky Lab. It has a graphical interface similar to Windows, allows you to select the desired language and perform a check of absolutely everything that is possible (including an in-depth scan of RAM). The only condition is to set the device with the recorded utility in the BIOS / UEFI parameters as the first to boot.
How to deal with ad viruses?
Now let's look at the manual removal of advertising virus applets. You can check your laptop for viruses and get rid of them using the following sequence of actions:
- detection of a virus process in the "Task Manager" with the location of files and folders;
- uninstall adware applet (if visible in programs and features);
- manual or software removal of residual components of the virus from the hard drive and from the system registry;
- restoring the search engine and the browser start page or completely resetting the browser settings;
- delete questionable browser panels, if any;
- remove prefixes in the path to the browser file through propertieslabel;
- reboot the system.

Note: sometimes intervention in the registry may be required even before the removal of the virus, and to remove the main application and its possible remnants, it is better to use special uninstallers. In case of lack of access rights to files and folders, the Unlocker utility sometimes helps.
How to check a phone for viruses through a laptop?
You can do the same with mobile technology as with stationary systems by installing the appropriate software on the device.

But if we talk about how to check a tablet or smartphone for viruses through a laptop by connecting them, for example, via a USB interface, it should be noted that the internal and removable drives of the device will be shown in Windows as ordinary removable drives if USB debugging was previously enabled. Verification tool is user's choice.
Last tip
Of course, these are only the main and most commonly used methods that allow you to check a laptop, desktop PC or mobile device for viruses. There are many more special programs designed for specific threats.

Finally, it remains to be added that installing such widely advertised applications on the Internet like SpyHunter is not recommended in any case, since without buying the full version of the package, it will be impossible to remove the found threats, and get rid ofthe program itself will be even more difficult and problematic than from the same adware.