Keep in mind to follow all solutions that have been listed in this guide accurately and also ensure to proceed in a step-by-step manner. To install Windows on this computer, restart the installation Windows Could Not Complete the Installation. To install Windows on this computer, restart the installation“. The error message that users get reads “ Windows Could not Complete the Installation. In this guide, we will be implementing some fixes that are aimed at completely getting rid of this error so that you are able to install the update on your computer normally. The Windows Could not Complete the Installation Error is seen by some users while trying to install an update on their computer or sometimes while trying to install the Windows OS on their computers.