diff --git a/distribution/windows/install.nsi b/distribution/windows/install.nsi
index d2658cd115..9a77e780e0 100644
--- a/distribution/windows/install.nsi
+++ b/distribution/windows/install.nsi
@@ -76,6 +76,7 @@ Var SHORTCUTS
 !define MUI_COMPONENTSPAGE_SMALLDESC
 !insertmacro MUI_PAGE_COMPONENTS
 
+!define MUI_PAGE_CUSTOMFUNCTION_LEAVE DoNotInstallInRCT2Folder
 !insertmacro MUI_PAGE_DIRECTORY
 
 ManifestDPIAware true
@@ -552,4 +553,12 @@ FunctionEnd
 Function un.onInit
 !insertmacro Init "uninstaller"
 FunctionEnd
+
+Function DoNotInstallInRCT2Folder
+    IfFileExists "$INSTDIR\Data\g1.dat" exists notexists
+    exists:
+    MessageBox MB_OK|MB_ICONSTOP `You cannot install OpenRCT2 to the same directory as RollerCoaster Tycoon 2.`
+    Abort
+    notexists:
+FunctionEnd
 ; eof