Before you touch anything: the safe-first order

Stop and look

Before clicking anything, read what is on the screen and write it down word for word, or take a photo of it with your phone. Note what you were doing when it happened.

Then ask: what changed recently? An update, a new program, a new printer or phone, a move to another room, a power cut. A recent change is often the cause.

Rule out the simple causes

• Is it plugged in, switched on, and is the cable pushed fully home at both ends?
• Is the monitor set to the right input, and is its brightness turned up?
• Is the sound muted, or going to a different speaker or headset?
• Is Wi-Fi switched on, and airplane mode switched off?
• Is the battery charged, and is the charger actually charging?

Restart properly

Save your work, then restart. A restart clears whatever the computer had got stuck on and fixes a surprising share of problems.

On Windows, choose Restart rather than Shut down and switching on again. With the Fast Startup setting on, which many PCs have by default, Shut down does not fully reset Windows; Restart does.

Change one thing at a time

Try one fix, check whether it helped, and write down what you did. If it did not help, put the setting back before trying the next thing. Changing five things at once means you never learn which one mattered, and you may create a second problem.

Know when to stop

• A burning smell, smoke, a swollen or hot battery, or liquid spilled inside: switch off, unplug, and do not switch it on again. This is a job for a repair shop.
• A hard drive that clicks or grinds: stop using it, because every minute of use can make data harder to recover.
• Anyone who contacted you first and asks for remote access or payment: stop. Module 3 explains why.
• Anything that needs the case opened, or a setting you do not understand: stop and get qualified help.