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Computer running slow?

There are a number of possible reasons that your computer is running slow and while you might be keen to understand exactly why, it isn’t always clear if your computer is suffering from just one or multiple issues. For Windows computers, there are a few typical reasons for lagging PC performance and the problem could be one of the following:

Your computer has run out of hard drive space

There are a few ways of finding this information depending which version of Windows you are using, but you can check your computer’s spec for free by downloading Speccy. If your computer’s hard drive is full, you should delete any unused programs to free up some space. You can do this quickly and easily using CCleaner’s uninstall tool, which can be found by clicking ‘Tools’ > ‘Uninstall’. It provides a list of installed apps by file size so you can delete items wasting most space first.

Your computer is clogged up with old cache and temporary files

Every time you use your computer it collects these files and if they’re not deleted, they can build up over time until they affect your PC’s performance. As well as using up space on your computer, these files can present a significant security risk in some situations. For example, Windows and many other programs will create lists of ‘recently used files’ to log your recent activities. This can be convenient for you if you want to retrace your steps. However, this information is valuable to hackers if malicious software is planted on your PC. Your computer doesn’t need these files and CCleaner can quickly, easily and safely delete them for you.

You have missed Windows updates or have outdated drivers

Although those reminders to update might seem like a pain, they exist for a valuable reason. Your PC needs to be kept up to date to ensure that it can perform normally, and that you are protected from malicious activities. Update reminders include those from Windows and from any installed software. To make the job of keeping up to date a bit easier, CCleaner has a built-in Software Updater tool, to update your apps in one go.


  • How do I fix a slow, freezing computer?

    If your computer starts slowing down, it could have too many temporary files and other junk in addition to too many programs clogging up your hard drive. Freezing might be caused by some undetected malware or hard disk errors.

  • How do I fix a slow hard drive?

    Many things can cause a hard drive to become slow including fragmented files on your drive, overloaded storage, disk errors and malware. How you fix it can also depend on which operating system you’re using.

  • What causes a computer to slow down?

    Computers can accumulate problems that cause them to slow down over time. These can range from overloaded hard drives and fragmented files to infrequent software updates, viruses, malware and more.