My Acer laptop running Windows has started freezing, and whenever I try to type, it sometimes enters a long string of plus signs like "++++++". A few days ago, two or three Command Prompt windows also appeared briefly and then closed when I turned the laptop on. I'm worried that I may have downloaded malware or a Trojan. What steps should I take to diagnose and fix this?
2 Answers
The brief Command Prompt windows and repeated plus signs could be caused by malware, but they might also come from a stuck keyboard key, a startup program, or a faulty driver. Start with a full scan using Windows Security under Virus & threat protection, then run Microsoft Defender Offline Scan if the first scan finds nothing. If the freezing continues, boot into Safe Mode. If the problem disappears there, a startup application or driver is probably involved.
Before assuming it’s a virus, check whether the plus key is physically stuck or whether something is pressing it. Try an external keyboard, disconnect any USB keyboards, and test the laptop’s keyboard in an online text field or BIOS. If the plus signs continue even when using another keyboard, then investigate software, malware, or driver problems.
I already have third-party antivirus software installed. Should I follow the same process, or use its scanning tools instead?