-Uninstall cubic castles from steam.
-Disable the antivirus for a few minutes.
-Download again Cubic Castles.
-We activate the antivirus again.
-Now we open the game and we wait for avast delete us the file *cubic.exe*.
-When avast deleted us the file cubic.exe, open the avast virus chest.
-Select the file which is below all.
-We click on the down arrow.
-They will leave us a few options, we click in *restoring*. (if it does no give you any option, returns to open the virus chest)
-Will leave us a notice that tells us: *The repaired file*.
-Now it only starts the game and ready.
PD: After all these steps, there may be the possibility that when you open the game for the second time you go the same error of avast, you must return to do the steps starting from the number 7.
If you have any questions please do not hesitate to tell me.
PD1.0: If you want i can make a video of this guide, for you to see if it works.