Damaged installations and files: If you’ve newly installed Microsoft 365 and Word won’t open the installation itself is possibly damaged.Windows updates and upgrades: Have you recently switched up your operating system to Windows 10? Then problems that occurred during the upgrade or update might be the reason for why Word won’t open.If Word does not launch after you install an add-in, this is most likely the cause. Word add-ins: Add-ins are extensions and offer practical additional functions for the word processing program.It is easier to check the most common errors and correct them if necessary. Word won’t start, but you can’t figure out why? In fact, it can be very difficult to find the cause if the program does not display an error message.