Minor not-important changes

Client/Core/SystemCore.cs

@@ -98,7 +98,7 @@ namespace Core
             }
             catch
             {
-                return 0;
+                return -1;
             }
         }
 

Server/Core/Build/ClientBuilder.cs

@@ -155,7 +155,7 @@ namespace Core.Build
                 case 3:
                     return 37; // System
                 default:
-                    return 26; // Appdata
+                    throw new ArgumentException("InstallPath");
             }
         }
     }