diff --git a/wine-tibbo/build.sh b/wine-tibbo/build.sh
index 6b35553dd6281d44f39756b44680c202014b4496..275772032618cdd3122301ba082872b1643aab7b 100644
--- a/wine-tibbo/build.sh
+++ b/wine-tibbo/build.sh
@@ -3,6 +3,12 @@ export DISPLAY=:0.0
 export WINEPREFIX="/home/vagrant/.wine"
 export WINEARCH="win32"
 
+# Install Mono for .NET 4.0
+apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF
+echo "deb http://download.mono-project.com/repo/debian jessie main" | sudo tee /etc/apt/sources.list.d/mono-xamarin.list
+apt-get update
+apt-get install -y mono-complete
+
 # Install WINE
 echo "deb http://httpredir.debian.org/debian jessie-backports main contrib non-free" >> /etc/apt/sources.list
 dpkg --add-architecture i386