Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab is one kind of archive. It is a Windows Cabinet file that is released for Speakonia, a text-to-speech program.

You may have faced this error during the startup of Speakonia or while using the program and don’t know what this means or what to do now. I would suggest you not panic because you can learn about this error and can easily fix it within a few steps. Please read the article to find the effective method to fix this error.

Reasons Why Microsoft Windows NETFX3 OnDemand Package – Runtime Error Occurs

The error mentioned above is called the Runtime errors because these errors occur during running the Speakonia program. The main symbol of this error is these errors are in the CAB extension.

Most of the CAB errors occur due to corrupted or missing files. These files can be missing for various reasons such as accidental deletion or detected as malware by the antivirus and deleted the file. The Runtime error also occurs when you start the Speakonia and the computer falls into a power outage or the system crash during loading the ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ file. The error screen is similar to the picture below:

Whatever the reason for this error is, you need to follow some simple steps and you will be able to fix this error on your own.

How to Fix ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ Error?

As you have encountered the ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ error, you need to follow a troubleshoot method step by step. This method of troubleshooting this error is given here according to the accurate order of execution. So, follow these methods one by one and you will be able to fix this issue. Here is the list of the methods to follow:

1. System Restore
2. Re-install Speakonia
3. Update Windows

Method-1: Perform A System Restore

Restore your system back to the time when the error didn’t exist on your computer. Here is the instruction to restore your system:

Step 1: Open the Windows Search box and type Recovery and press Enter.

Step 2: Click on Open System Restore from the options.

Step 3: Select the restore point and click Next.

Step 4: Follow the procedure to restore your computer back to the date when there were no Runtime errors.

If this fails to fix the ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ error, then follow the next method to fix this.

Method-2: Re-Installation of the Speakonia Software

Sometimes the Speakonia software may be corrupted or faulting the installation can cause this ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ error. So, to get rid of this error, you need to uninstall the software and install the latest version of it. Follow the instructions to reinstall it:

Step 1: Press Windows + I key simultaneously to go to the Settings and click on Apps. 

Step 2: Then, find the Speakonia software and click on it.

Step 3: Then click Uninstall and follow the further procedures to uninstall it.

After successfully uninstalling the software, restart your computer and reinstall the Speakonia software. Now, check if the error is existing or not. Hopefully, you won’t see the error this time. But if it still exists, then follow the next method below.

Method-3: Perform A Windows Update

If you failed to fix the ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ issue using the first two methods, then it is worth trying to update your windows to fix this. According to the report of many users, an outdated window may also cause this runtime error. To update your Windows, follow the instruction below:

Step 1: Click on the Search icon and type Update.

Step 2: On the search results, click on Check for Update

Step 3: On the destination, click on the Check for updates button and wait a while until it finds some updates.

Step 4: Download and install updates from here.

Step 5: After successfully completing the update it will inform you that a restart is required. Click on the Restart now button.

After your computer turns on, check for the runtime error. If this also fails to fix the issue, then you have to go through an advanced troubleshooting method which is only for Advanced PC users only.

Advanced Troubleshooting: Download and Replace The ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ File

CAUTION: This process is not for amateur computer users. Any mistake during this process can damage your Windows Operating System completely and have to reinstall a clean Windows. So, backup your important documents and data before starting this process.

If none of the above methods can fix the issue with your computer, then you have to replace the ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ file on your computer. Follow the instructions carefully to download and replace the file:

• Identify the version of your operating system and download the ‘Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab’ file according to your OS.
• Download your file by clicking the Download button.
• Now move the downloaded file to the appropriate location of the Speakonia folder. Here is the navigation – 

Windows 10: C:\$WINDOWS.~BT\Sources\sxs\

• Finally, restart your computer.

This method is supposed to fix the error completely. On the other hand, it can drop you into a permanent error if you have done anything wrong during the process. In that case, you have to perform a reinstallation of Windows on your computer.

Frequently Asked Question

What Is Microsoft Windows NetFx3 OnDemand Package CAB?

If a specific file is missing, moved, or accidentally deleted from its original installed location of Windows 10 Features on Demand x86’s, then the Microsoft-windows-netfx3-OnDemand-package.cab error occurs. It is also called Runtime error as it shows errors during the running program. It can be resolved by replacing the CAB file (CABinet file) from its location.

How Do I Install .NET 3.5 Manually On Windows 10?

You will need an internet connection first. Then press the ‘Windows’ key on your computer and on the search bar, type ‘Windows Features’. Then click on the Turn Windows Features On/Off from the result list. After that, fill in the .NET Framework 3.5 (includes .NET 2.0 and 3.0) check box and click OK. Finally, perform a restart and you will have successfully installed the .NET 3.5 on your computer.

How Do I Fix Error 0x800F081F?

To fix error 0x800F081F, open the Group PolicyEditor and navigate to Configuration > Administrative Templates > System. Then, double-Click on Specify settings for optional component installation and component repair. Finally, click on the Enable button.

Conclusion

I hope you have now understood what Microsoft-Windows-NETFX3-OnDemand-Package~31bf3856ad364e35~AMD64~En-Us~.Cab is and how to fix this error. As this error occurs because of the missing or damaged file, it can be easily solved by replacing that file. However, this is a critical process and that’s why this process is included at the end of this document. You are recommended to apply the first three methods in the beginning to avoid risk.

You should backup your important, data, documents, images, videos, applications, and other things to a secure place like a USB device or portable hard disk before performing these processes.