diff --git a/os/os2/installer/make_installer.cmd b/os/os2/installer/make_installer.cmd
--- a/os/os2/installer/make_installer.cmd
+++ b/os/os2/installer/make_installer.cmd
@@ -1,6 +1,6 @@
 @echo off
 
-set OPENTTD_VERSION=1.0.0-beta3
+set OPENTTD_VERSION=1.0.0-beta4
 set OPENSFX_VERSION=0.8.0
 set NOSOUND_VERSION=0.8.0
 set OPENGFX_VERSION=0.7.0