Scan a suspicious computer with a clear plan
Malwarebytes can inspect a Windows computer for malware and potentially unwanted programs, then let you review detected items and take action. It is useful when you want a second investigation of suspicious behavior, unexpected advertising or an unfamiliar download. Slowness alone does not prove an infection, and a clean scan does not establish that every part of a system is trustworthy. Treat the report as evidence to interpret alongside the symptoms.
The distinction between Free and Premium matters. Free provides on-demand scanning and removal of existing detections. Premium adds ongoing real-time protection and other preventive features according to the plan. An introductory trial may temporarily show paid capabilities; check the status inside the application instead of assuming those capabilities remain free forever. A free scan is not the same thing as continuous background protection.
Download and check current requirements
The verified Windows release is 5.7.3. Current requirements are Windows 10 or Windows 11, at least 4 GB of memory and 1 GB of free space at installation. The publisher recommends 8 GB of memory. S mode must be disabled, and an active internet connection is required for installation and software, component and database updates. Older Windows 7 or 8 installations should not be treated as supported by the current build.
Use the official Malwarebytes download page and save the installer locally. Run it, verify the publisher prompt and follow the setup choices. Select the intended personal or organizational use where requested and review any optional offers or plan choices. A separate macOS edition exists, but its requirements and features differ; this Windows guide does not describe that installation.
Update, scan and inspect the report
Once the application is ready, let its detection data update before starting a scan. Save any open work, then begin the recommended scan offered by the current interface. Scan duration depends on the system and selected scope. Avoid interpreting a shorter scan as proof that nothing was examined, or a longer one as proof of an infection. What matters is the completed report and any actions requested.
Read the detection names and paths before approving cleanup. Potentially unwanted software and confirmed malicious files are not identical categories, and a file you recognize may still need investigation. Quarantine isolates an item so it cannot be used normally while it remains under review. Do not immediately restore a detected file simply because an application asks for it, and do not empty quarantine before understanding what was detected.
Check the result beyond the scan window
Restart if the program requests it and confirm whether the original symptom has stopped. Save the report if further troubleshooting may be necessary. Repeated detections can need a more specific investigation; continually deleting the same items without understanding their return is not a complete solution. If account credentials may have been exposed, account recovery and password changes from a trusted device are separate tasks.
O&O ShutUp10++ changes Windows privacy settings and does not remove infections. BleachBit cleans selected temporary data rather than acting as an antivirus. Use those tools only for their separate purposes, after deciding whether a security issue is present. Keep Windows and applications maintained and retain backups: no single scanner can guarantee complete protection or reverse every consequence of an attack.
