8 steps to fix APC INDEX MISMATCH BSOD like a pro

BSOD errors can be rather troublesome on Windows 10, and in most cases these types of errors are caused by an incompatible driver or a faulty hardware.

Windows 10 users reported having APC INDEX MISMATCH BSOD error, so let’s see how to fix it.

What is error APC INDEX MISMATCH?

APC_INDEX_MISMATCH error can cause many problems since it will force your PC to restart whenever it appears. Speaking of this error, users reported the following issues:

• Apc index mismatch Lenovo, Dell – This error can appear on almost any device, and both Lenovo and Dell users reported this error. If you encounter this error on your PC, you should be able to fix it by using one of our solutions.
• Apc index mismatch blue screen, BSOD, crash – APC_INDEX_MISMATCH is a blue screen error and like any other blue screen error, it will force your PC to crash whenever it appears. However, you should be able to fix this problem by updating your drivers.
• Apc index mismatch Windows 7, Windows 8 – This error can appear on every version of Windows, and even if you’re using Windows 7 or Windows 8, you should be able to fix the problem using one of our solutions.
• Apc index mismatch ntoskrnl.exe, fltmgr.sys, wdf01000.sys, win32k.sys, vhdmp.sys – This error message will sometimes give you the name of the file that is responsible for this error. Once you know the file name, you need to do a bit of research and find the application or driver that is related to this file.
• Apc index mismatch Realtek, Nvidia – Several users reported that Realtek and Nvidia devices can sometimes cause this error to appear. If that’s the case, be sure to update your drivers and check if that solves the problem.
• Apc index mismatch Windows 10 update – Sometimes this problem can occur after installing a specific update. To fix the issue, it’s required that you find and uninstall that update from your PC. After doing that, the problem should be resolved.
• Apc index mismatch overclocking – Many users reported this problem after overclocking their hardware. If you have overclocked your hardware, be sure to remove overclock settings and check if that solves the issue.

Steps to fix APC INDEX MISMATCH errors

1. Disable Realtek HD Audio Manager from starting
2. Install the latest updates
3. Check your drivers
4. Uninstall the DisplayLink driver
5. Remove certain software
6. Change your RAM frequency
7. Disable Virtualization in BIOS
8. Check your hardware

Solution 1 – Disable Realtek HD Audio Manager from starting

Sometimes APC INDEX MISMATCH error can be caused by a certain application or a driver that is installed on your PC. A number of users reported that they are unable to access Windows 10 at all because they would get a blue screen just after logging it.

Since there’s no way to access Windows 10 regularly, in order to disable a certain application from starting you’ll have to access Safe Mode. To access Safe Mode do the following:

1. While your computer boots, restart it. You’ll have to restart it a few times before the Automatic Repair starts.
2. Windows should automatically start the repair process. Choose Troubleshoot > Advanced options > Startup Settings. Click the Restart button.
3. Once your computer restarts again, you’ll see a list of options. Press F5 or 5 to select Safe Mode with networking.

Once you’ve entered the Safe Mode, you can stop the problematic application from starting by doing the following:

1. Start Task Manager. You can start it by pressing Ctrl + Shift + Esc on your keyboard.
2. After Task Manager starts, navigate to Startup tab.
3. You’ll see a list of startup apps. If you see Realtek HD Audio Manager on the list, right click it and choose Disable. If that application isn’t on the list, disable all applications from starting with Windows 10.
   
4. Close Task Manager and restart your PC.

Solution 2 – Install the latest updates

According to users, sometimes you can fix APC INDEX MISMATCH error simply by installing the latest updates. This error can appear if your current version of Windows isn’t compatible with your hardware or with a specific software.

In most cases, you can fix this problem simply by installing the latest Windows updates. To make this process more streamlined, Windows 10 will download the updates in the background automatically.

However, sometimes you might miss an important update due to certain bugs. However, you can always check for updates manually by doing the following:

1. Press Windows Key + I to open the Settings app. Now navigate to Update and Security section.
   
2. Now click Check for updates button.
   

Windows will now check for available updates. If any updates are available, they will be downloaded automatically in the background. Once you download the updates, they will be installed as soon as you restart your PC.

Several users reported that they fixed this problem simply by installing the latest updates, so be sure to try that.

Solution 3 – Check your drivers

Error APC_INDEX_MISMATCH can sometimes appear after you install a new device on your PC. Sometimes the driver isn’t fully compatible with your computer and that can cause this error to appear.

To fix this issue you’ll have to make sure that the installed device is using the latest drivers in order to avoid compatibility issues. To update the device drivers, do the following:

1. Optional: If you cannot access Windows 10, enter the Safe Mode and go to Step 2.
2. Start the Device Manager. You can do that by pressing Windows Key + X and choosing the Device Manager from the list.
   
3. Once the Device Manager starts, locate the newly installed device. If you see an Unknown Device, or any device with a yellow triangle, you’ll need to update its drivers. You can do that right from Device Manager by right clicking the device and choosing Update driver. In addition, you can also download the latest drivers online.
   

If you wish to keep your Windows 10 PC error-free, we strongly advise that you update all your drivers. Updating drivers manually can be a long process, but you can use this Driver Update software to update all your drivers with just a single click.

• READ ALSO: Fix error code 0xc004c003 in Windows 10

Solution 4 – Uninstall the DisplayLink driver

A number of users reported that this issue was caused by DisplayLink drivers. DisplayLink is useful when you have an additional monitor, but unfortunately, it seems that there are certain issues with the DisplayLink driver and Windows 10.

In order to fix this problem, you’ll have to remove the DisplayLink software from your PC. To do that, follow these steps:

1. Open Control Panel and navigate to Programs and Features.
   
2. Locate DisplayLink Core software on the list and uninstall it.
3. After you’ve uninstalled it, restart your computer.

In order to completely remove DisplayLink driver you need to download and run DisplayLink Installation Cleaner. After using this software, Display Link driver should be completely removed and the APC_INDEX_MISMATCH error should be fixed.

Solution 5 – Remove certain software

Software such as LogMeIn can cause APC_INDEX_MISMATCH error, therefore it’s advised that you update it or remove it from your PC. In addition to LogMeIn, certain antivirus software, most notably Norton and Avast can cause this issue to occur.

If you’re using any of these antivirus programs, we urge you to remove them by using the Norton Removal Tool or Avast Cleaner.

If you don’t use any of these tools, you should still try removing your antivirus software and check if that solves the issue. If you’re planning to switch to a different antivirus software, we already covered the best antivirus programs for Windows 10, so you should check them out.

If your antivirus is the problem, you might want to consider switching to a different antivirus software. There are many great antivirus tools, but the best are Bitdefender, BullGuard and Panda Antivirus so feel free to try any of them.

All these tools offer great protection and they are fully compatible with Windows 10, so feel free to try any of them.

Solution 6 – Change your RAM frequency

This is an advanced solution, and by performing it you might cause damage to your PC. Changing the RAM frequency might lead to system instability if not done properly, so bear in mind that you’re doing this at your own risk.

If your motherboard cannot handle the frequency of your RAM, it’s advised that you remove any overclock settings that you have. Alternatively, you can underclock your RAM so it can match your motherboard frequency.

To do that, you’ll need a proper overclocking tool, and we already did a list of best overclocking tools for Windows 10, so make sure to check it out.

Solution 7 – Disable Virtualization in BIOS

According to users, this problem can appear due to Virtualization feature. Several users reported APC_INDEX_MISMATCH error while using Trend Micro tool on their PC.

It seems that Virtualization feature is interfering with Trend Micro and causing this problem to appear. To fix the problem, it’s advised to do the following:

1. Enter BIOS. To do that on your PC, you need to press Del or F2 during the boot sequence.
2. Once you enter BIOS, you need to find and disable Virtualization feature. To see how to locate this feature, you might want to check your motherboard manual for detailed instructions.

After disabling this feature, check if the problem is resolved. If you don’t have Virtualization feature available in BIOS, you can skip this solution entirely.

Solution 8 – Check your hardware

As previously mentioned, BSOD errors can appear due to faulty hardware, and APC INDEX MISMATCH is no exception. According to few users, the problem was caused by a faulty touchpad on their laptop, and after replacing the touchpad the APC INDEX MISMATCH error was resolved.

If your device is still under warranty, you might want to consider taking it to the official repair shop for a hardware replacement.

APC_INDEX_MISMATCH can cause you a lot of trouble, but fortunately this Blue Screen of Death error can be easily resolved by using one of our solutions.

FAQ: Learn more about APC INDEX MISMATCH BSOD

• What is an APC index mismatch?

It is an error causes by a driver incorrectly performing an APC (Asynchronous Procedure Call). If you are interested in fixing this read our APC index mismatch fix guide.

• How do I fix Irql not less or equal?

A similar, common BSoD is IRQL NOT LESS OR EQUAL. To fix this you need to perform a clean boot and see if the error shows again. This will let you know if the problem is a service or program that is usually running. Otherwise, try disabling the Cache Memory from the BIOS.

• Is blue screen of death bad?

The error means that a critical bug was encountered by one of the main Windows processes and it couldn’t continue operating. Thus, this type of error can be considered bad since it interrupts your operations and sometimes it can lead to data loss.

Editor’s Note: This post was originally published in June 2016 and has been since completely revamped and updated in April 2020 for freshness, accuracy, and comprehensiveness.