Do not suggest reformatting the hard drives!
Either you do not have enough RAM, An html/java file can be corrupt, the download could be corrupt, etc.
First thing to do:
Does it show an error message? If yes, google the message.
If it does't show an error message, run task manager and see if the exe is even running. If it's not, it's likely been stopped by the antivirus or by windows.
If it is running but is not responding, it could be looking for a driver, stuck in a loop, or waiting for a timeout. Give it a few more minutes and be patient. If it does not respond at all, kill it and then ask in the General Troubleshooting section thread how to debug your game. Be specific, list all steps taken, and first of all, be patient!
And remember it's usually not necessary to reformat the hard drive unless you have malware that cannot be removed.. It shortens your hdd life every time you reformat. It's best to do weekly defrags to improve hdd life and improve program response slightly.
Could google "Can't run RPG Maker MV game"????