how to manually remove MSI installation?

I am learning VS 2008 setup project to create install for our C# application. I made a mistake trying to delete the exe itself during the uninstall. Now I manually deleted the exe file but the entry still in Add Remove Program list. I try to install a fixed newer version but msi doesn't allow me to do so.

How can I remove the old version manually (i can use regedit, no problem)? I am using XP machine. thanks

EDIT: После того как я удалил его подраздел в этой записи реестра для удаления, я все еще не могу установить свою новую версию.