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 maybe 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 techie and enjoy 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, but you also must make sure that before installing the hardware, it is compatible with the Windows version that is installed into your computer.
Use Compatible software. If the problem was caused by software or a driver, you can uninstall and reinstall it. Always make it a rule that whenever you install a program or 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 that 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 In most cases though, the cause of the APC_INDEX_MISMATCH error are outdated device drivers.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 manufacturer's 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 on 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.

“Operation could not be completed (error 0x00000643)”
Error CausesDisk Write Error in Steam is thrown at you while you try to download or update the game in your library. If you are an unfortunate user of Steam that has encountered this error do not sweat, the error is usually tied to permission in windows or file corruption and not to hardware issues and can be easily resolved.
In this guide, we will go through solutions for this specific error and it is advisable to go through solutions as they are presented since they go from the easiest and most common issues.

The easiest and quickest way of resolving this issue is just a simple restart of the Steam client. Just completely quit Steam and they run it again, if this has not solved the issue try rebooting your PC. In most cases, this can solve the issue since this error is known to be introduced with some communication issues with OS (Windows)
Disk write permissions could also cause this error because if by any chance the Steam library folder has been set or changed to the read-only client would be unable to write anything in it. To easily solve this issue completely exit the Steam client and rerun it as administrator. Just right-click on it and select Run as Administrator. If this has solved your issue run Steam always as an administrator.
To run always as an administrator right click on the steam executable, go to properties, and inside properties go to the compatibility tab. In the compatibility tab check run as administrator and click on OK.
If for any reason cache has become corrupted there is a big chance that this might be an issue why there is a disk drive error in Steam. To clear download, cache goes into your client, and on top drow down menu click on steam. Find and open settings and inside go to the downloads tab. Locate a clear download cache and immediately you will be prompted to restart Steam. After restart, you will be asked to login into steam and the issue with disk write should be gone.
Library folder issues can also be the source of disk write annoyance so let's repair them. Click steam in the top left and go to the settings. Locate and click on Downloads and then go to Steam library folders. You will be here shown all disk drivers you are using for steam games and all of the games that are downloaded.
Select the game you are getting errors with and click on three dots on the far right. From the menu choose the repair folder option. Take note that the more games you have installed, the more time the repair process will need.
Sometimes the issue is not at your end at all, servers can experience problems and outrages and this can directly reflect at your end with a disk write error. If any of the previous solutions have not resolved the issue this is the next logical step to try. If the server is facing issues then changing the download server will resolve the issue at your end.
Click on settings in the top drop-down menu and then click on the Steam library folder. Find the downloads page and then click on download region, Choose another server than one nearest to your location since that's what will Steam choose by default.
VSSControl: 2147467259 Backup jobs failed. Cannot create a shadow copy of the volumes containing the writer’s data. VSS asynchronous operation is not completed. Code: [0x8004231f]This message pops up when you are creating a snapshot system restore, usually, the issue is tied with insufficient space or service stopping. We will go into detail about how to fix both so you can finish the operation without any issue.
chkdsk /f /r
powercfg /hibernate /size 100
Error Causes
Error Causes