求教高手 关于使用自定义可视用户对象问题

小弟正在做毕业设计,其中自定义了一个可视用户radiobutton控件,保存后,当使用该控件时报错
inherit failed
inherit of u_radiobutton failed.possidle causes:
1-object does not exist
2-objext is already open in another
userobjext painter
3-user objext control in object is already open in another user object painrer


小弟急求!