hey, dont know if you managed to fix this or not but i had the same issue and found a solution.
Im using Windows 10 64bit and recently bought a MSI GTX 1070 Gaming X 8gb. Upon installing MSI gaming App, it would work until i restarted my Pc and then the app would not load ever again unless i uninstalled and reinstalled.
I found that the services needed for this app was not running. When i started both GamingApp_Service and MSI_ActiveX_Service the program would load.
To permanently solve the issue -
Windowskey+r then type %SystemRoot%\system32\compmgmt.msc and press enter
Select Services and Applications
Click Services
Right Click GamingApp_Service and select properties
Set Startup type to Manual
Rinse and repeat for GamingHotkey_Service and MSI_ActiveX_Service
Your Gaming App will now start up when opened, whether manually or automatic upon windows login (if you have it set to.)
Hope this helps.