My browser has been closing by itself while I'm away, and the history shows activity I didn't perform, including an attempted donation to an orphanage, attempts to access my bank account, and a search for "card." Malwarebytes detected and removed Trojans and spyware, but the browser closed again later and suspicious activity continued. I've disconnected the computer from the internet and am changing my passwords. Could someone still access the computer remotely while Windows is locked, and should I completely reinstall Windows? What other steps should I take to protect my accounts and data?
4 Answers
A clean Windows installation is the safest approach when you suspect a remote-access Trojan or an infostealer. Back up only essential personal documents, not executable files or recently downloaded installers, then erase the system drive and reinstall Windows from official installation media. Reinstall applications only from their legitimate sources and fully update Windows afterward.
Treat files downloaded around the time the suspicious behavior began as potentially infected. Don’t copy unknown programs, cracks, scripts, or installers to the new installation. Scan any necessary documents separately and make sure your backups predate the suspected infection if possible.
Keep the computer disconnected from the network for now. From a different, trusted device, change important passwords, enable two-factor authentication, and contact your bank or card providers so they can monitor the accounts and replace cards if necessary. Assume the machine may still be compromised even after a malware scan.
Remote access can happen if malware or a remote-management tool is already running, even when the desktop is locked. Disconnecting the machine limits what an attacker can do, but it doesn’t remove the infection, so account protection and a fresh installation are more reliable than repeated scans alone.

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