6 Ways to Resolve Blue Screen Error APC Index Mismatch in Windows 10 [Complete Guide]

Imagine being engrossed in a crucial task on your computer, such as drafting an important document, and you're just moments away from the deadline. Suddenly, your computer freezes, and all you're left with is a haunting blue screen displaying an error message that reads "APC Index Mismatch" or the error code APC_INDEX_MISMATCH.

Normally, the BSOD (Blue Screen of Death) occurs due to malfunctioning hardware, incorrect configurations, or incompatible drivers. Unfortunately, you may lose some data in this scenario, but it can be fixed as long as you identify the main issue. Therefore, you need to pinpoint the problem area and either disable or remove it, or try alternative solutions based on the cause.

Here are some top solutions you can implement when this error message appears on Windows 10:

Fix 1: Uninstall Update

The APC Index Mismatch Windows 10 issue might arise when you're using an outdated system. However, it could also happen after updating your Windows version, potentially due to unforeseen errors or compatibility issues.

In this relatively uncommon scenario, you need to uninstall the recent update. Firstly, verify if the error emerged following the device's upgrade. Subsequently, roll back to the previous version and wait for newer updates to become available.

Step 1. Tap on the Windows icon located at the bottom left corner of your screen to open the Start menu. Then, choose Settings.

Or, you can press the Win + I keys on your keyboard. Alternatively, type "Settings" in the search bar and click on the first option.

Step 2. On the tiles that appear, choose Update & Security.

Step 3. Next, click on the Windows Update option in the left-hand navigation bar.

Step 4. Click on "View update history" in the next window.

Step 5. Tap on the Uninstall Updates option and wait for the PC to remove all recently installed updates.

Solution 2: Try to Roll Back to a Previous Version of Windows 10

When users upgrade their computer from an older version, such as Windows 8.1 to Windows 10, the older version remains in the hard drive memory. This older version is typically removed after approximately 28 days. If the APC Index Mismatch error occurs during this period, you can revert your device to the previous version to resolve the issue.

Step 1. If your computer isn't plugged into a power outlet, do that now. Then, tap Next.

Step 2. Click the Start icon on your taskbar, then type "recovery" in the search field.

Step 3. Select "Recovery options (System settings)" next.

Step 4. On the next Recovery screen, tap on Go back to Windows [X]. The [X] represents the previous Windows version that your system had.

Step 5. Choose the reason for the rollback and click Next.

Step 6. Tap the 'Go Back to Windows [X]' button. Afterwards, follow all the rollback-related instructions displayed on the screen. Upon successful completion of the process, your system will automatically restart into the previous Windows version.

A simpler way to roll back to a previous version of Windows is by using a free system rollback software like Todo Backup. With just a few straightforward steps, you can easily revert to the desired version of Windows.

Solution 3: Check the Drivers on Your Computer

One possible cause of the "APC Index Mismatch Windows 10" error message is the presence of incompatible peripheral devices connected to the system, such as an external webcam. This issue can occur when the installed device does not match well with the current drivers. To resolve this problem, you should inspect all the drivers to identify the incompatible one and update it.

Step 1. Press the Win + X keys on your keyboard. From the options, select Device Manager.

Step 2. Locate the recently installed device from the list of drivers. When you find one with a yellow triangle or labeled as Unknown Device, right-click on it and select Update Driver.

Step 3. Wait until the installation process is complete.

Alternatively, you can revert to the previous, compatible driver by double-clicking on it and navigating to the Driver tab > Roll Back Driver > OK.

Select the reason and tap on YES. Afterwards, restart the device.

Solution 4: Check RAM Frequency in Task Manager

One of the advanced methods to address the APC Index Mismatch issue involves checking your RAM frequency using the Task Manager. However, it's important to note that incorrect execution of these steps might lead to system instability. Therefore, opt for this solution only if other methods fail or if you possess the necessary technical expertise.

Step 1. Open the Windows 10 Taskbar and right-click on it. From the context menu, select Task Manager.

Step 2. In the following window, tap on the Performance tab and select Memory to view RAM-related information such as utilized slots, RAM speed/frequency, total memory used/available, and so on.

At times, the APC Index Mismatch issue can occur due to actively running Trend Micro tools. This happens because of virtualization feature-related issues within the system that interfere with the normal operation of other system utilities. To resolve this, you should disable this setting in your BIOS.

Solution 5: Disable Virtualization Technology

At times, the APC Index Mismatch issue can occur due to active Trend Micro utilities. This is often a result of virtualization feature-related problems within the system that interfere with the normal operation of other system tools. To resolve this, you should disable this setting in your BIOS.

Step 1. Tap the Windows icon to open Start.

Step 2. Press the Power button > Restart. This will shut down all running functions on the device.

Step 3. While the device is booting, press F2 on the keyboard. This may vary for some laptop/computer models. Other possible keys you can try are F10, F8, F12, or the Del key.

Step 4. When the BIOS screen appears, navigate to Advanced > disable the Virtualization feature. Afterwards, restart your device once more.

Fix 6: Reset or Reinstall Windows 10 If none of the previous solutions work, you might need to resort to resetting or completely reinstalling Windows 10 as a last resort. This will erase all your personal files, apps, and settings, so make sure to back up your important data before proceeding. To reset your Windows 10 PC: 1. Go to the Start menu and click on the gear icon to open Settings. 2. In the Settings app, select "Update & Security." 3. From the left pane, choose "Recovery." 4. Under "Reset this PC," click on "Get started." 5. You'll be given two options: - "Keep my files": This option will remove apps, settings, and updates, but keep your personal files. - "Remove everything": This option will erase everything, returning your PC to the original factory state. 6. Choose the appropriate option and follow the on-screen instructions to complete the process. If resetting doesn't work, you can also perform a clean installation of Windows 10: 1. Download the Media Creation Tool from Microsoft's official website. 2. Run the tool and choose to create installation media for another PC. 3. Follow the prompts to create a bootable USB drive or ISO file. 4. Restart your computer and boot from the USB drive (you may need to change your BIOS settings to do this). 5. Choose "Install Windows" and follow the steps to install a fresh copy of Windows 10. Remember that these steps will likely resolve any software-related issues but may also require you to reactivate your Windows license and reinstall all your applications.

The final solution to resolve the APC Index Mismatch issue is to reinstall or reset your Windows 10 PC. Resort to this step only if none of the previous methods prove effective. Keep in mind that resetting your device can result in the deletion of various system configurations, personal files, and applications, so view this as a last-ditch effort.

Step 1. Click on the Start button from the Windows icon in the taskbar, and then select Settings.

Step 2. Select Update & Security > Recovery.

Step 3. When you see the Reset this PC option, tap on Get Started > Remove Everything.

Conclusion

Indeed, there are various strategies to address the APC Index Mismatch error in Windows 10. Initially, it might stem from incompatible drivers or updates, which you should uninstall. If that's not the root cause, examine deeper issues, such as a BIOS problem involving the Virtualization feature. Alternatively, consider resetting your entire system if none of these solutions resolve the issue. Lastly, if the hardware problem is complex, seek professional technical assistance.