ESET Online Help

Search English
Select the topic

Computer scan

The On-demand scanner is an important part of your antivirus solution. It is used to perform scans of files and folders on your computer. From a security standpoint, it is essential that computer scans are performed regularly as part of routine security measures, not just when an infection is suspected. We recommend that you perform regular in-depth scans of your system to detect viruses that are not captured by Real-time file system protection when they are written to the disk. This can happen if Real-time file system protection is disabled at the time, the detection engine is obsolete, or the file is not detected as a virus when it is saved to the disk.


Two types of Computer scan are available. Scan your computer quickly scans the system without specifying scan parameters. Custom scan (under Advanced scans) enables you to select from pre-defined scan profiles designed to target specific locations and choose specific scan targets.

See Scan progress for more information about the scanning process.


By default, ESET Security Ultimate attempts to clean or delete detections found during the computer scan automatically. In some cases, if no action can be performed, you receive an interactive alert and must select a cleaning action (for example, delete or ignore). To change the cleaning level and for more detailed information, see Cleaning. To review previous scans, see Log files.

ICON_SCAN Scan your computer

Scan your computer enables you to quickly launch a computer scan and clean infected files with no need for user intervention. The advantage of Scan your computer is it is easy to operate and does not require detailed scanning configuration. This scan checks all files on local drives and automatically cleans or deletes detected infiltrations. The cleaning level is automatically set to the default value. For more detailed information about cleaning modes, see Cleaning.

You can also use the Drag and drop scan feature to scan a file or folder manually by clicking the file or folder, moving the mouse pointer to the marked area while keeping the mouse button pressed and then releasing it. After that, the application is moved to the foreground.

The following scanning options are available under Advanced scans:


Custom scan lets you specify scanning parameters such as scan targets and methods. The advantage of Custom scan is that you can configure the parameters in detail. Configurations can be saved to user-defined scan profiles, which can be useful if scanning is repeatedly performed with the same parameters.

ICON_REMOVABLE_SCAN Removable media scan

Similar to Scan your computer—quickly launch a scan of removable media (such as CD/DVD/USB) that are currently connected to the computer. This may be useful when you connect a USB flash drive to a computer and want to scan its contents for malware and other potential threats.

This type of scan can also be initiated by clicking Custom scan, selecting Removable media from the Scan targets drop-down menu and clicking Scan.

ICON_REPEAT_SCAN Repeat last scan

Enables you to quickly launch the previously performed scan using the same settings as before.

Action after scan drop-down menu enables you to set an action to be performed automatically after a scan finishes:

No action—After a scan finishes, no action will be performed.

Shut down—The computer turns off after a scan finishes.

Restart if needed—The computer restarts if only needed to complete cleaning of detected threats.

Restart—Closes all open programs and restarts the computer after a scan finishes.

Force restart if needed—The computer forces restart if only needed to complete cleaning of detected threats.

Force restart— Forces closing of all open programs without waiting for user interaction and restarts the computer after a scan finishes.

Sleep—Saves your session and puts the computer in a low-power state so that you can quickly resume working.

Hibernate—Takes everything you have running on RAM and moves it to a special file on your hard drive. Your computer shuts down but will resume its previous state the next time you start it.


Sleep or Hibernate actions are available based on your computer Power & sleep operating system settings or your computer/laptop capabilities. Remember that a sleeping computer is still a working computer. It is still running basic functions and using electricity when your computer runs on battery power. To preserve battery life, for example, when traveling outside of your office, we recommend using the Hibernate option.

The selected action will start after all of the running scans are finished. When you select Shutdown or Restart, a confirmation dialog window will display a 30-second countdown (click Cancel to deactivate the requested action).


We recommend that you run a computer scan at least once a month. Scanning can be configured as a scheduled task from Tools > Scheduler. How do I schedule a weekly computer scan?