Follow the steps below to fix QuickBooks error 15222
Install a digital signal certificate:
In the initial stage, we have to shut down the QuickBooks Desktop. It should be done in the initial stage because if Quickbooks is open, then the Digital Signature tab will not be seen.
In the next step, we have to do right click on QBW32.exe which is located in C:\ Program Files\ Intuit \ QuickBooks and select Properties.
Then we need to click the Digital Signature tab. In this case, it should be made sure that Intuit, Inc. is chosen in the signature list.
The next step will be to select Details and in the Digital Signature Details window, we should click on View Certificate.
Then in the Certificate window, Install Certificate should be clicked on.
We should keep on clicking the “Next” button until the message “Finish” is popped up.
After the full procedure, restart the computer, open QuickBooks and download the update again.
I hope these steps will be helpful!