Windows Running Slow or Acting Up? Try These 7 Fixes First

If your Windows PC is running slower than it used to, throwing random errors, or just acting weird — don’t panic. Most common issues have straightforward fixes that don’t require a trip to a repair shop or a full reinstall. Here are seven things to try first, in order.

1. Restart the Right Way

This sounds too simple, but it matters how you restart. In Windows 10 and 11, clicking Shut Down doesn’t fully power off the machine — a feature called Fast Startup saves a snapshot of the system state to speed up the next boot, which can carry over problems.

The fix: Use Restart instead of Shut Down. Restart does a full memory clear and gives Windows a clean slate. If you can’t restart through the Start menu, hold the power button for 10 seconds to force a hard shutdown, then power back on.

2. Check Task Manager for Resource Hogs

A slow PC is often caused by one program eating up all your CPU, RAM, or disk activity in the background.

The fix:

  1. Open Task Manager using one of these two shortcuts:
    • Ctrl + Alt + Delete, then click Task Manager from the menu that appears
    • Ctrl + Shift + Esc to jump straight to Task Manager without the extra menu step — if the first shortcut isn’t working, try this one
  2. Click More details if you see the compact view
  3. Click the CPU, Memory, or Disk column headers to sort by usage
  4. Look for anything near the top that seems suspicious or that you don’t recognize

Common culprits: antivirus scans running in the background, browser extensions, Windows Update downloading in the background, or a program that didn’t close cleanly. Right-click → End Task to kill a process temporarily. If it keeps coming back, that’s worth a deeper look.

3. Run Windows Update

Outdated Windows versions can cause slowdowns, compatibility issues, and security vulnerabilities. Windows 10 officially reached end-of-life in October 2025, so if you’re still on it, you’re no longer receiving security patches — which is a real risk.

The fix:

  • Go to Settings → Windows Update → Check for Updates
  • Install everything pending, then restart
  • If you’re on Windows 10, seriously consider upgrading to Windows 11 if your hardware supports it

To check compatibility, Microsoft’s PC Health Check app will tell you if your machine can run Windows 11.

4. Run the System File Checker (SFC)

Windows has a built-in repair tool that scans for corrupted or missing system files and tries to fix them automatically. This is surprisingly effective for random crashes, error messages, and general instability.

The fix:

  1. Search for Command Prompt in the Start menu
  2. Right-click it and choose Run as Administrator
  3. Type: sfc /scannow and press Enter
  4. Let it run — it can take 10–20 minutes
  5. Restart when it’s done

If SFC finds and fixes issues, you’ll see a message saying so. If it can’t fix something, it will tell you that too. In that case, you can escalate to DISM (Deployment Image Servicing and Management) — a more powerful built-in Windows tool that repairs the system image that SFC pulls its repair files from. Think of SFC as the mechanic and DISM as the parts supplier: if the parts are corrupted, the mechanic can’t fix anything until the supply is restored. To run it, open Command Prompt as Administrator and type: DISM /Online /Cleanup-Image /RestoreHealth and press Enter. Let it finish completely, then run sfc /scannow again afterward.

5. Check Your Disk Space

Windows needs free disk space to operate — for temporary files, virtual memory, and updates. If your C: drive is nearly full, performance tanks.

The fix:

  • Open File Explorer, right-click your C: drive, and check free space
  • If you’re under 10–15% free, it’s time to clean up
  • Run Disk Cleanup (search for it in the Start menu) and check all boxes including system files
  • Consider moving large files (photos, videos) to an external drive or cloud storage

6. Update (or Roll Back) Your Drivers

A bad driver update — especially for graphics, network, or storage — can cause freezes, crashes, or strange behavior right after an update.

Note: Only do this step if you are experiencing a specific hardware issue — such as video problems, network connection issues, or external storage not being recognized.

The fix:

  • Right-click the Start button → Device Manager
  • Look for anything with a yellow warning icon
  • Right-click it → Update driver or Roll back driver if the problem started after a recent update

For graphics drivers specifically, go directly to the manufacturer’s website (NVIDIA, AMD, or Intel) rather than relying on Windows to find the latest version. Look for the support section or drivers section and then locate the driver for the model of your graphics card. You can find your computer’s system information by going to Control Panel → System and Security → System. This is also the Settings menu screen mentioned earlier in step 3.

7. Scan for Malware

Malware doesn’t always announce itself. Some of it quietly runs in the background, consuming resources, sending data, or causing random instability.

The fix:

  • Windows Defender (built-in) is actually solid for most threats. Open it from the Start menu → Windows Security → Virus & Threat Protection → Quick Scan
  • For a second opinion, download Malwarebytes Free and run a scan alongside Defender
  • Avoid running two real-time antivirus programs simultaneously — that causes conflicts — but running a one-time scan with a second tool is fine

The Troubleshooting Mindset

These seven fixes cover the majority of everyday Windows problems. My approach — shaped by years of PC repair work and earning my CompTIA A+ — is always to start simple and rule things out systematically before jumping to conclusions. A slow PC rarely needs a reinstall. It usually needs a restart, a scan, and 20 minutes of attention.

Work through the list in order, restart between steps, and see what changes. If you get through all seven and still have problems, that’s when it’s worth digging deeper.

If any of this sounds familiar — if you grew up somewhere analog (mechanical age) and ended up somewhere digital — you’re in the right place. Come join the conversation in the Hooked On Gaming | Programming or DC Global Bots, Gaming & Trading Discords. You can also check out our YouTube Channel where I share videos of creators that I like and will begin to share videos of my own; Sly’s Analog and Digital Chronicles. I’d love to hear your story too.