diff --git a/proton b/proton
index 6f383429..ed5b1d23 100755
--- a/proton
+++ b/proton
@@ -1006,6 +1006,7 @@ class Session:
         self.dlloverrides = {
                 "steam.exe": "b", #always use our special built-in steam.exe
                 "dotnetfx35.exe": "b", #replace the broken installer, as does Windows
+                "dotnetfx35setup.exe": "b",
                 "beclient.dll": "b,n",
                 "beclient_x64.dll": "b,n",
         }