On the fourth boot, a blue screen appeared—not a crash, but the screen. She clicked Advanced Options > Troubleshoot > Advanced Options > Startup Settings > Restart .

When the laptop rebooted, a list of numbered options appeared. She pressed on her keyboard for “Enable Safe Mode.”

She forced her laptop off by holding the power button for 10 seconds. She turned it on. As soon as the HP logo appeared, she held the power button again to force another shutdown. She repeated this .

In Safe Mode, she ran a quick antivirus scan (which found and removed a rogue driver update), then used System Restore to roll her Pavilion back to a point from last week.