The error – 0x80070490 occurs when Windows users 

• Try to carry out a Windows update
• While they upgrade the Windows system. 
• Try to buy or install an application via the Windows Store.
• Due to virus/spyware/adware attack or misconfigured system files

There are several fixes you can try to resolve the error and here are some of them

Try running – Windows update troubleshooter

Windows Update Troubleshooter is a useful troubleshooting utility that allows you to fix problems related to updates. 

• Use your keyboard and press- Win logo key and then type – troubleshoot.
• Now click – Troubleshoot
• Click on -Windows update–run the troubleshooter.
• Perform the instructions given on the screen
• Now restart your system and check if the error has vanished

Run SFC scan utility 

SFC (System File Checker) is a useful tool in Windows that scans your system for corrupted or missing files. It automatically repairs the corrupted system files (it includes data related to – error 0x80070490).

• Using your keyboard only press – Windows logo key and then type – cmd. Now, right-click – Command prompt and run as administrator.
• To confirm click – Yes 
• Type – sfc /scannow in the command prompt window and hit enter
• It takes a while for the tool (SFC) to restore corrupted files with new files in case any corrupted files are found. You need to be a little patient and wait for the scanning process to get over
• Now restart your PC and verify if the error 0x80070490 is fixed.

Run DISM

Deployment Image & Servicing Management (DISM) is also a useful tool to resolve errors caused by corruption

• Use your keyboard and press – Windows logo key.
• Type –cmd and click – Command Prompt 
• Next – Run as administrator.
• Wait for some time for the process to get over 
• Now, type -sfc /scannow and hit enter

Now, restart your machine and try to carry out the update once again and check if it works fine.