Prevent PC Freezes

Prevent PC Freezes

PC keeps locking up or behaving sluggishly? Discover how to prevent your computer from randomly freezing

If you're constantly plagued by your computer locking up, or by programs failing to respond, what can you do about it? Before calling in the experts, see if you can track down a cause (and solution) for your problem with the help of these FAQs.

How do I shut down a frozen program?
If a program stops responding, try clicking its red close button to see if it will close itself down. If you're unable to click the red close button (the program window may flash) then check the next Q&A. Otherwise, wait 30 seconds to see if the program closes itself properly before clicking the button again. Windows should notify you that the program has stopped responding, giving you the option of forcibly closing it.


Hidden dialogue boxes can prevent programs from closing themselves.

Why can’t I click on the close button?
When you open a program's dialogue box, such as the Open/Save box, it can occasionally get hidden behind other windows, making it impossible to continue using a program until that box has been cleared.

To try and resolve this, roll your mouse over the misbehaving program's Taskbar icon and wait for the Aero Peek preview window to pop up. Select each preview window in turn to see if a dialogue box appears, then click it to bring the box to the front. If this doesn't work, first try switching to another program, then return to the non-responsive program. Alternatively, press [Win] + [M] to minimise all open windows, then click the program's Taskbar icon to see if the dialogue box is revealed. If you still can't get to the close button, read on.


Task Manager is a special Windows tool you can use to close non-responsive programs.

I can't close the program using either of the above methods. What next?
Windows has a special tool called Task Manager that – among other things – lets you examine running programs and processes and close them in emergencies. Try right-clicking the taskbar and choosing Task Manager from the pop-up menu; if this doesn’t work, press [Ctrl] + [Alt] + [Del] and select Task Manager from the list.

This should bring up a list of running programs. Select the misbehaving program from the list and click End Task, then wait as before. If nothing happens, try clicking it again and Windows should bring up the non-responding dialogue box, giving you the option of forcibly closing the program.

That had no effect. What can I try next?
Windows 8 users should click More Details, then right-click the troublesome program and choose Go to Details; Windows 7 users should right-click the troublesome program and choose Go to Process to switch to the program’s entry under Processes or Details. Try clicking End Task again.

If this fails to work, try saving all open documents in other programs and trying again; if this fails, try restarting your PC.


Each browser tab you open consumes valuable system resources – don’t overdo it!

What can I do to prevent PC freezes?
First, ensure that your PC isn’t overloaded with too many programs and processes competing for limited system resources.

  • Start by reining in your web browser: you’re asking for trouble if you regularly leave it running all day with loads of tabs and windows open as it can quickly gobble up all available memory. You’ll make things even worse if you also install every plug-in or extension under the sun. An overloaded browser consumes more resources and is more prone to crashing or freezing, so take the time to keep things to a minimum: don’t open too many tabs at once, disable unwanted plug-ins and get into the habit of closing the browser down for 30 seconds or so every few hours, just to clear things out.
  • Try to keep the number of running programs down to a minimum – avoid having more than three or four open at the same time.
  • Take the time to perform a thorough disk clean-up following our top tips here. Cutting the number of programs that start with Windows, plus defragmenting your hard disk, will have the biggest effects on sluggish performance.

My PC is running smoothly, but crashes still occur. What else can I do?
If the problem keeps occurring with a specific program, first check that it’s up to date. Some programs perform this check each time they run, but also look on the program’s Help or About menu for an option to manually check for an update, and install any that are offered.

If you can’t find an update option, or the problem continues to occur, visit the program’s website and look in the Support section for further help, either in the form of an update or a knowledge base or user forum where you can see if the problem is a known one, and how to fix it.

What other problems can cause PC crashes?
Malware infections can be an underlying cause for sluggish behaviour and frequent crashes. Make sure your security tools are up to date and run full scans with them to make sure, plus follow our guide to identifying and removing malware from your PChere

Malicious software is also a prime cause for freezes and crashes.

Could my hardware be faulty?
Malfunctioning hardware can also cause Windows problems, and many manifest themselves by way of system lock-ups or a blue error screen before your PC restarts itself. Isolated incidents can usually be ignored, but if the problem continues, then you need to investigate further.

One common hardware fault is damaged memory. Windows has a built-in memory diagnostics tool – Windows 7 users can access it by clicking Start, typing ‘memory’ into the Search box and clicking Diagnose your computer’s memory problems. Windows 8 users will find the same tool by opening the Search charm, typing ‘memory’ into the Search box and selecting Settings. Follow the prompts and – if any errors are found – take steps to replace the faulty memory.

Other potential hardware causes to consider: an overloaded power supply, which can usually be traced to a recent hardware upgrade, a failing hard drive (use CrystalMark Disk Info to check) or cooling issues related to dust, clogged fans or inadequate ventilation.