Laptop Slow After a Windows Update? How to Fix It

Windows has installed an update, and since then your laptop has been painfully slow. It takes ages to start, programs hang with "Not responding" in the title bar, and the fan won't stop. If you open Task Manager, you may see Disk sitting at 100%, or a message in Windows Update saying "Restart required" or "Pending install".

Sometimes this settles down by itself within a day. If it doesn't, this guide walks you through the fixes, easiest first, and helps you decide whether the laptop just needs tidying or is genuinely near the end of its life.

Why This Happens

After a big update, Windows has a lot of housekeeping to do in the background:

• Finishing installation, which may need one or more restarts.
• Rebuilding the search index, so Start menu searches work.
• Running a security scan with the updated Microsoft Defender.
• Updating apps from the Microsoft Store and drivers.

On a modern laptop with an SSD, this is barely noticeable. On an older laptop with a traditional spinning hard drive (HDD), or one that's nearly full, it can make the machine almost unusable for hours. Updates can also expose existing problems, such as too many programs starting with Windows or a drive that's failing.

Fix 1: Let It Finish and Restart Properly

1. Plug the laptop in and leave it on (with the lid open) for an hour. Background tasks pause on battery.
2. Go to Settings > Windows Update and install anything waiting. If it says Restart now, do so.
3. Restart, rather than shut down. On many laptops, Shut down uses Fast Startup and doesn't fully clear things out. Choose Start > Power > Restart.
4. Check Settings > Windows Update > Advanced options > Optional updates for driver updates from your laptop's manufacturer.

Fix 2: See What's Slowing It Down

Press Ctrl + Shift + Esc to open Task Manager. On the Processes tab, click the CPU, Memory or Disk column header to sort by it.

• Disk at 100% for long periods: usually the hard drive struggling. See Fix 6.
• Memory above 90%: too much open at once, or not enough RAM for modern Windows.
• One app hogging CPU: if you recognise it, close it. If you don't, search its name from another device before ending it.

Fix 3: Turn Off Startup Apps

Many programs set themselves to launch every time Windows starts, and they add up.

1. In Task Manager, open Startup apps (in the left-hand menu on Windows 11).
2. Look at the Startup impact column.
3. Right-click anything you don't need straight away (updaters, chat apps, music apps, manufacturer extras) and choose Disable.
4. Restart.

Fix 4: Free Up Storage

Windows needs breathing room. If the main drive is nearly full, everything slows down, and future updates may fail.

1. Go to Settings > System > Storage and see how much space is free.
2. Click Temporary files and remove what's suggested. After a big update, Windows Update Cleanup or previous Windows installation files can take up a lot of space. Only remove previous Windows installations if you're happy with the update, because it removes the option to go back.
3. Turn on Storage Sense on the same page so Windows clears temporary files automatically.
4. Check Settings > Apps > Installed apps and uninstall programs you no longer use.
5. Move large photo and video folders to an external drive or cloud storage. If you use OneDrive, turn on Files On-Demand so files stay online until you need them.

Fix 5: Check for Malware

Slowness alongside pop-ups, a changed browser homepage or unfamiliar programs can indicate malware.

1. Open Windows Security > Virus & threat protection.
2. Click Scan options, choose Full scan and run it. It can take an hour or more.
3. If anything is found, follow the prompts to remove it, then run a Microsoft Defender Offline scan from the same page for good measure.

Be wary of any pop-up claiming your computer is infected and asking you to call a number. That's a scam. See our guide to the fake virus warning pop-up.

Fix 6: Check What Kind of Drive You Have

This is often the real answer for laptops more than five or six years old.

1. Open Task Manager and click the Performance tab.
2. Click Disk 0. In the top right, or under the graph, it will say SSD or HDD.

If it's an HDD, the drive is almost certainly why Disk sits at 100% after updates. Modern Windows is designed with SSDs in mind. Many older laptops can be upgraded to an SSD, which can make them feel dramatically faster, provided the rest of the machine is in reasonable shape.

Signs of a failing drive include clicking noises, files that won't open and very long freezes. If you notice those, back up your important files immediately.

When It's Time to Replace the Laptop

An upgrade isn't always worth it. Consider replacing the laptop if:

• It can't run Windows 11, so it will stop receiving security updates.
• It has 4GB of RAM or less and can't be upgraded.
• The battery, screen or keyboard are also failing.

Our new laptop setup checklist covers what to do when you get a new one.

When to Get Help

If the laptop is still slow, you're worried about losing files, or you'd like an honest view on whether to upgrade or replace it, our computer repair service can diagnose it, upgrade drives and memory, and move your files safely. Many slowdowns can be fixed through remote support anywhere in the UK. Senri Home engineers visit across West and South West London seven days a week, 8am to 9pm. Book a visit or call or WhatsApp 07826 399715.

Related Reading

• New Laptop Setup Checklist: What to Do First
• Fake Virus Warning Pop-Up? Don't Call the Number
• Printer Says Offline? How to Fix It on Windows and Mac