» APC_INDEX_MISMATCH  – What is it and how to fix it? - Error Support for Windows PCs

The error 0x0000001 also known as APC_INDEX_MISMATCH is one of the fatal errors that users encounter upon starting their computers. This error appears when there is a sequence mismatch in the driver or system file when it is disabling or re-enabling Asynchronous procedure calls. The mismatch happens may be because of a virus or malware attack, not shutting down your computer properly and incomplete installation of the system files.

There are many ways to fix this error. The easiest way is to download a repair utility program. The use of these programs perfectly fits those that are not so technical. All you have to do is download the program and install it on your computer. As soon as it is installed, the program will now scan and diagnose your computer for any errors. After it identifies the errors, it will then repair your PC through either manual or automatic tools.

To those who are a techie and enjoys the manual resolution, you may take advantage of Microsoft’s !analyze debug extension which tells you the cause of the error. After determining the cause then you can now start fixing the error.

Check if Hardware is functioning properly. If the cause is due to a hardware malfunction, you will have to make sure that all the pieces you are using are working. All the wires should be attached to their respective ports. Not only that, you also must make sure that before installing the hardware, it is compatible with the Windows version that is installed into your computer.

Use a Compatible software. If the problem was caused by a software or a driver, you can uninstall and reinstall it. Always make it a rule that whenever you install a program or a new software to your computer, make sure it is compatible with your operating system and never skip a step during the installation process. You also have to see to it that the program you are installing does not contain any viruses, malware or spyware which can be harmful to your computer.

Update your Drivers Regularly. In most cases though, the cause of the APC_INDEX_MISMATCH error are outdated device drivers. To resolve this, you will have to go to your Control Panel then look for Device Manager. As soon as you are in the Device Manager window, you can now see the different devices running on your computer. You right-click on each device and check the Properties.  In the Properties window, click on the Driver Tab and look for the date when it was last updated. You can then go to the manufacturer’s website and compare the dates.

For a new Windows operating system, you no longer have to go to the manufacturers website though. All you have to do is click on Update Driver and it will automatically search for updates online.

Use a Genuine Operating System. There are also cases where the 0x0000001 error won’t allow you to access your computer. In this case, we have to suspect that the problem could be in your Operating system. To resolve this, you can reinstall your Operating System or update your current operating system. Only use a genuine licensed Windows Operating System because this will not only protect you from Malware and Viruses but it allows you to get all the recent update available from Microsoft. Update your Windows 10 regularly by going to Settings > Windows Update > Check for Updates. You may also turn on the Automatic Update by going to the Advanced options is found in the Windows Update Page.

You can always get help online but it really helps to know the basics and determining the root cause of the error.