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Discover how to fix 100% disk usage issues in Windows 11:  This is how you do it!

If you use data-hungry graphics or video editing programs, you’ve probably run into the issue where your computer just doesn’t want to process the sheer amounts of data anymore.  

But even if you don’t work with vast amounts of data, your PC may slow to a snail’s pace — like surfing the internet back in the early days when you had to wait ages for a response. The culprit: 100% disk usage.  

Read on to learn how to fix 100% disk usage issues in Windows 11 more quickly and easily — and how you can use Avira System Speedup for Windows to prevent your PC’s hard drive from being worked to the max..      


What is 100% disk usage? 

In Windows 11, 100% disk usage means that your laptop or PC’s hard drive is fully utilized and can no longer execute any further commands or process data. This means that the system becomes very slow, responsiveness to inputs such as mouse clicks and keystrokes are massively delayed, and the system might even crash.   

100% disk usage has a similarly negative impact on your PC’s performance as excessive CPU utilization. 

CPU (processor) utilization, on the other hand, describes the proportion of working time one or more of your PC’s main processors is actually processing productive tasks. 

Don’t confuse maximum disk usage with hard disk space either (in other words, the storage capacity of your hard disk), because 100% disk usage always relates to the main memory or RAM (random access memory).  

What’s the culprit behind maximum disk usage? 

A few things may be causing 100% disk usage in Windows 11:  

  • Unnecessary or incorrect system processes 
  • Faulty or outdated drivers 
  • Corrupt file systems  
  • Malware 
  • Persistent demanding disk usage. 

You might have guessed that 100% disk usage has little to do with your computing habits, because maximum disk utilization can happen even on new devices with all the required updates. 

How to identify the causes of 100% disk usage 

There are several ways to find out why your computer is experiencing maximum disk usage and why your PC is freezing. To do this, you can do the following to get to the bottom of things through a process of exclusion: 

    1. Quit unnecessary programs and their processes. To do this, press the Ctrl, Alt, and Del keys simultaneously and then open Task Manager.
      Under Processes, you can see exactly which programs are using the most disk power. Orange fields in the Disk column are a good place to look, because any process that exceeds 1 to 2 megabytes per second (MB/s) can be critical. While it’s normal for disk usage to spike for very short bursts of time, it should drop back down to around 20%.    
    2. Disable Windows Search, as this service can sometimes be very demanding on your hard drive. You’ll find Windows Search in the Control Panel under Services. 
    3. Also disable the Windows service Superfetch because this service, which is designed to speed-up access to frequently used files, sometimes causes high disk usage. To disable this service, press the Windows and R keys simultaneously, then enter net.exe stop superfetch in the input field.
    4. Check the hard drive for errors by entering chkdsk C: /f /r in the prompt, provided your PC’s hard drive is labeled C:. Otherwise replace the C: with your hard drive’s letter
    5. Check that you also have the latest drivers installed, as even outdated drivers can cause high disk usage
    6. Run a virus scan — if you don’t do this regularly — to ensure your PC isn’t infected with malware. It’s best to use a tried-and-tested antivirus program like Avira Free Antivirus for Windows


Also remember to first back up your data so you don’t lose important files. 

Use optimization tools 

If you want to make things easier for yourself, consider using an optimization tool for Windows. Avira System Speedup for Windows is one such optimizer. It can help you find and fix the causes of 100% disk usage, plus you benefit from a whole range of helpful tools at your disposal, including: 

  • Power cleaner, to help find things like registry errors or temporary files like junk files that can cause excessive disk usage. 
  • Maintenance tools, to help you find outdated drivers and fix Windows issues. 
  • Upgrade to Avira System Speedup Pro, and you also get to use Disk Doctor. It can help you in many ways, including finding out if a disk error is causing 100% disk usage.  
Avira System Speedup for Windows
Troubleshooting 100% disk usage issues with the optimization tool Avira System Speedup for Windows.

Why is 100% disk usage bad? 

We’ll go into more detail below about the consequences of 100% disk usage, but before we do: It affects performance, can damage your hard drive, lead to data loss and, in the worst case, even cause your PC to fail completely. 

It saps performance 

When your hard drive is fully utilized, it can cause your computer to slow down significantly or even freeze. While your PC is trying to read or write files, other processes or apps continue to run at the same time, slowing down response times immeasurably — something that clearly reduces device performance. 

It can damage your hard drive 

Persistent, very high disk usage can cause your hard drive to age faster. If it’s constantly subjected to excessive stress, this can cause a range of issues, including mechanical ones which might even lead to hard drive failure. 

There is a risk of data loss  

If your PC’s hard drive is used to 100%, it can lead to data loss. If insufficient disk space is available, programs and critical system processes cannot function properly. And of course you won’t be able to save any files either. 

How to avoid 100% disk usage 

As you’ve already learned from this post, there are a number of reasons why your computer’s hard drive is at 100% utilization: Too many programs running at the same time, a defective hard drive, or even malware running in the background. But did you know that restarting your PC cleans up the RAM and can even help to prevent maximum disk usage? 

Install antivirus software 

As we’ve mentioned, one of the main causes of high disk usage can be malware. Therefore, run a virus scan regularly to ensure your PC is free of viruses, Trojans, and other malware that may cause maximum disk usage. 

You shouldn’t just rely on Windows Defender, which is preinstalled with the operating system on your computer. The latest virus scanners are designed to protect your Windows PC from different types of malware, because they can better address the latest cyberthreats. 

Disable start-up programs 

Many of us don’t even realize when starting our PCs that a number of programs that aren’t actually needed launch in start-up mode, adding to your 100% disk usage woes. Top tip: Disable the programs you don’t need right away the moment you start using your computer.  

It’s easy to do: Press the Ctrl, Alt, and Del keys simultaneously and then open Task Manager. Under the Startup apps tab, you’ll find all the programs listed here that are launched when the computer starts up, meaning they start and remain active in the background. Now simply right-click the relevant program and select Disable from the drop-down menu. 

Update your drivers  

If your laptop or PC’s drivers are outdated, performance will suffer and, in the worst case, the programs installed on your computer as well as your system won’t run smoothly. Once again, Avira System Speedup for Windows can be a great help, since this optimization tool can help you find outdated drivers.  


Make sure there are no hard disk errors  

Because a defective hard disk can also cause 100% disk usage, it’s best to check it regularly by pressing the Windows and R keys simultaneously then entering chkdsk C: /f /r in the prompt.  

If you already use Avira System Speedup Pro, you can also use the Disk Doctor. It makes it easier for you to better rule out hard disk errors as the cause of excessive utilization. 

Practice good file management 

A large number of files and a really high degree of file fragmentation can also cause your hard drive to work overtime. As such, manage your files carefully and use defragmentation tools regularly to tune up your hard drive.  

You can do this using Windows system tools — or you can use Avira System Speedup Pro to defragment your hard drive regularly, ideally weekly.  

Adjust your virtual memory 

Both Windows 10 and Windows 11 swap out rarely used areas of the main memory to the swap file pagefile.sys. They use this virtual memory to create space for system components and active processes.  

This automatic size management process for paging files provided by Windows is actually a clever memory management method where RAM is increased as required during operation — but it’s also considered to be a performance brake. 

Windows 11, for example, requires at least 4 GB of RAM. And if you use several programs at the same time, this need increases (Google Chrome in particular requires a lot of memory). When your PC’s RAM is at maximum utilization, the virtual memory moves unneeded data to your hard drive to free up memory in RAM — and also pushes it back into RAM as soon as you need that corresponding data. 

If you have an older computer with limited RAM, adding more RAM can help avoid excessive disk usage by providing enough memory to run programs. Follow these three simple steps to get started: 

Step 1: Open the Settings app, then scroll down and select About. 

Step 2: Under Device specifications, now click Advanced system settings. 


Step 3: In the System Properties dialog box that opens, the Advanced tab should already be preselected.
Click the first Settings button.  


Step 4: In the Performance Options dialog window that now opens, select the Advanced tab at the top and then click Change… under the Virtual memory section. 

Step 5: In the new Virtual Memory dialog window, first untick Automatically manage paging file size for all drives and select Custom size. 

Step 6: For the Initial size value, enter the recommended size (it’s displayed a bit further down in the dialog window). The value for the maximum virtual memory size should be around 1.5 times the size of your RAM. For example, if you have 4 GB (4096 MB) of RAM, the maximum value should not exceed 6 GB (6000 MB). Then click OK. 

Disable Windows Search indexing 

Windows 11’s search feature is a powerful tool to quickly find files, settings, or even online content. Windows records all entries via an indexing service in the background so that search queries lead to results as soon as you type them. 

This constant process of indexing involves repeatedly moving large amounts of data, which can also lead to 100% disk usage. However, the downside of completely disabling Windows Search indexing is that searching for files in the system can take longer. 

Step 1: Enter Services in the search field and search for Windows Search in the list that opens.  

Step 2: Right-click Windows Search and select Stop from the drop-down menu.  

Read our blog post for information on scanning and repairing Windows hard drives with CHKDSK.

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