As you know, Windows Hello offers you quick access to computers since you can log in to your Windows devices three times faster compared to passwords with the help of the camera via Face recognition and fingerprint reader. This way, Windows Hello will recognize you right away. However, there are also times when you might encounter some problems when using Windows Hello. For one, if you are trying to add the PIN method to Windows Hello on your Windows 10 computer but you suddenly encountered an error code of 0x801c004d or if you are trying to use your existing pin and you encounter an error code of 0x80070490 along with an error message that says, “Not recognized”, then read on as this post will guide you on how you can fix both of these errors. Here is the complete content for both errors:
If you got any of these two errors, there are several potential fixes you can check out to resolve them. You can try to check for any Windows Updates or create the PIN again or check the CNG Key Isolation Service. You could also try to reset the TPM or create a new User Account. For more information, follow the instructions provided below.
The first thing you can do is to check for any available Windows Updates. It is possible that your computer may be outdated and is the reason why you’re having troubles with Windows Hello. To check for Windows Updates, just go to Settings and from there, head over to the Update and Security section and click on Windows Updates located on the left pane, and then click on the Check for Updates option. Wait until the process of checking updates is completed and if it finds new updates, install it. After you install the new Windows Updates, check if you can now add the PIN on Windows Hello or not.
The next thing you can do is to create the PIN again by signing out and signing in again and then try creating the PIN once more. If this does not work, you can try restarting your computer and creating the PIN again. You could also try removing the PIN and then change it.
The CNG Key Isolation Service is the one that stores and uses long-lived keys in a secure process complying with the common criteria requirements and it is possible that the error could be related to this service. This service is hosted in the LSA processes and provides key process isolation to private keys and associated cryptographic operations as required by the common criteria. Thus, you need to check this service to see if it’s the one that’s causing the error.
You might also want to try resetting the Trusted Platform Module or TPM to fix the error. You can do this by opening Windows PowerShell and then executing the “Clear-Tpm” command. After that, check if the error is now resolved.
You could also try to create a new User Account on your Windows 10 computer to fix the Windows Hello error. Once you have created a new local user or administrator account in Windows 10, check if you are now able to add the PIN from this newly created user account.

If the Error Code 0xC004C770 popped up on your computer during your activation of the Windows 10 software, don’t worry. This is a fairly common error, especially for people who own more than one computer upon which Windows 10 is installed and activated. The gist of this error code is that the product key that you have entered has already been claimed or used on a different computer. Because there are limitations on the number of computers that can use any given license activation code or product key, this error code can arise when you have exceeded that limit. If you have a single-use license and have already entered the particular product key onto another machine, you may see this error come up during activation.
Both Error Code 0xC004C770 and Error Code 0x803FA071 arise from the same problem and the same steps can be used to resolve both error codes.
Error CausesError Code 0xC004C770 is likely to appear on your screen during activation of Windows 10 if you or anyone else in your organization have already entered in the product key used on another computer. If you have a multiple-use license, the product key that you are entering may already have been used for the maximum number of computers allowed under that license.
There are two basic methods for addressing the issues associated with Error Code 0xC004C770. These methods can easily be implemented by anyone who is comfortable interacting with the Windows Store from their computer, which makes the resolution of this particular error code fairly simple and straightforward.
If you are unable to complete the steps below or Error Code 0xC004C770 has not been resolved after following the guides below, contact a Windows technician who is familiar with the Windows 10 activation process to assist you in the process. You can also get in touch with the Windows technical support team to assist you in the process if needed.
If you have already used the product key on another computer or have used it on the maximum number of allowed devices, you may need to purchase an additional product key for the computer with Error Code 0xC004C770. Product keys can be purchased physically from a retailer that sells Windows 10 software licenses or purchased directly from the Windows store.
To purchase a new product key directly from the Windows Store, follow the steps below:
If you are unable to see the “Go to Store” option when you reach the “Activation” page, you may not be set as an administrator of your machine. In this case, get in touch with the support personnel from your company to complete the purchase, installation, and activation process on your computer.
For users who have changed out parts of their computer’s hardware, like putting in a new motherboard or activating a new hard drive, you may have more success if you attempt activation through a phone.
In order to activate your copy of Windows 10 from your phone, follow the steps below:
As with any error code resolution, if the methods above are not successful or if you are not comfortable with your ability to successfully complete the steps above, get in contact with a qualified professional who is trained in the Windows 10 activation process to assist you or download a powerful automated tool to get the job done.
Error CausesCheck your connection. Microsoft Store needs to be online. It looks like you’re not. Check connection Code: 0x80072F7DThis is the error that you get if trying to open the Microsoft store on Windows 10 and it fails. If you experienced this error and are unable to access the store do not despair we are here to help you. This particular error is usually due to some internet issues, follow the presented guide step by step in order to solve it and be able to access the Windows store again.
CHKDSK [volume [[path] filename]] [/F] [/V] [/R] [/X] [/C] [: size]]Note: In the command given above, “[/F]” will try to fix the system errors while “[/R]” will be the one to fix the bad sectors.
Are you trying to update your Windows 11 OS and are receiving a 0x800f0905 error? Do not sweat and do not worry we have a couple of solutions that you can try in order to fix this issue. How this error is tied to various things like misconfigured settings, corrupt system files, and more there is no way to present one simple solution that will solve everything in one click.
Therefore we are presenting a couple of solutions that will fix your issue, it is advisable to follow them as presented since they will go from the most common to the more complex one.
The most common fix and one that will actually repair things most of the time is simply running the Windows Update troubleshooter.
If the previous solution did not work we will need to do things manually. Follow the steps as presented in order to reset Windows update components.
Well, that was a lot of typing or copy and pasting line by line followed by ENTER after each one but hopefully, your issue is solved. These provided solutions fixed most users' issues with this error but if for some reason this is not the case for you, move to the next step.
If you are still having 0x800f0905 error after previous attempts do the following:
If for any reason previous solutions have not provided you with the solution we will try to fix the issue by performing system restore.
If for any reason Windows still cannot install the update, try installing it manually.
If nothing worked, reset your Windows 11 to its factory settings to fully repair and reset the whole operating system.