Is there a patch for windows vista will allow you to run mideavel lords build defend expand

Yes! things I did which together made it work...
Update your graphics card drivers
Go to the GSP / Avantsoft website and look up the game in their FAQs
There is file to download www.gspsupport.co.UK/media/patches/Medieval_Lords.exe
1. Save the file Medieval_Lords.exe to your desktop
2. Right click on the Medieval_Lords.exe on your desktop and left click 'Cut'
3. Go to Start | Run, type in or Browse to C:\Program Files\Monte Cristo\Medieval Lords and click on OK
4. Please right click in this folder and left click 'Paste', this will ask you to replace the Medieval_Lords.exe , click 'Yes' .
NB If it doesn't ask you to replace it (i.e. the original wasn't there, then look in one of the subfolders - Mine was in /Bin. Replace that and run it from there.