Openrct2.exe crashed, deleted itself and cannot be replaced

[Yukabacera]

I just started the game. I was in the main menu, checking the version of the servers, but suddenly the game exited and the .exe file disappeared. Now I can't even replace/update the game, because I get a "this operation requires permission" error (I don't know the exact error message, I use hungarian windows, sorry :c)
What can I do now?
(Sorry for bad english)
Edit: I can paste/move the new .exe file anywhere on my computer, just not into that folder. I can also paste/move any .exe file into my RCT2 folder (except this one)
Edit 2: It seems Avast has put the .exe (original) file into quarantine, but I can't restore it

Edited June 29, 2018 by Yukabacera
More info

[jensj12]

Looks like your antivirus (Avast) is treating OpenRCT2 like a virus. The only way to fix this is to somehow tell Avast that OpenRCT2 is not a virus. You can try to whitelist OpenRCT2 to prevent any future interventions of Avast.

[Yukabacera]

It's working now, thanks!