diff --git a/openttd.dsp b/openttd.dsp
--- a/openttd.dsp
+++ b/openttd.dsp
@@ -103,6 +103,10 @@ SOURCE=.\ai\default.c
 # End Source File
 # Begin Source File
 
+SOURCE=.\ai\ai.c
+# End Source File
+# Begin Source File
+
 SOURCE=.\ai\trolly\pathfinder.c
 # End Source File
 # Begin Source File
@@ -498,6 +502,10 @@ SOURCE=.\ai\trolly\trolly.h
 # End Source File
 # Begin Source File
 
+SOURCE=.\ai\ai.h
+# End Source File
+# Begin Source File
+
 SOURCE=.\aystar.h
 # End Source File
 # Begin Source File
diff --git a/openttd.vcproj b/openttd.vcproj
--- a/openttd.vcproj
+++ b/openttd.vcproj
@@ -887,6 +887,12 @@
 			Name="AI Files"
 			Filter="">
 			<File
+				RelativePath=".\ai\ai.c">
+			</File>
+			<File
+				RelativePath=".\ai\ai.h">
+			</File>
+			<File
 				RelativePath=".\ai\default\default.c">
 			</File>
 			<Filter