Now i know there are a lot of topics about this already. But I think i know what the cause is in my case.. I just dont know how to solve it.

I was going to install Conquest of the new world on my other computer. When i was downloading i noticed i was on my girlfriends account. At that moment I got a Windows request or something that i denied.. When i switched to my other account i got this Installation failed disk acces problem error.

I tried restarting, deleting the local files, restarting pc. Anybode has a clue how to solve this in my case?

W10
HDD + SSD

Download the offline backup installers and install that way. Then you can sync it with Galaxy and update the files if necessary.