So you are excited in installing Windows 10 and tried downloading the Windows 10 free upgrade, but once the download was finished, you were greeted by the error 80240020 in Windows Update. The reason for the error is that the installation files that you have downloaded were either incomplete or corrupt, probably due to the overload of Microsoft Servers. To fix this error or for any other reason, just want to force Windows 10 to install manually (e.g. Media Creation Tool keeps on failing.), follow the procedure below.
Warning: The quick fix method below requires you to modify the registry. Note that when modifying the registry incorrectly, serious problems might occur. So before doing the “Windows 10 force install trick”, it might be wise to back up your registry first.
1. Open “regedit”.
You can do this by hitting “Windows key + R”, then typing “regedit”, and pressing Enter.
Or, if using Windows 8, pressing the Windows key and typing “regedit”, then press Enter.