我的VB Active Dll 不能被PB访问，为什么? 详情。。。

OLEObject PcsCustom
PcsCustom = CREATE OLEObject
PcsCustom.ConnectToNewObject("IRSDefect")
opensheet(w_doc,main)
main.dialog1.object.showopen
String temp
temp=PcsCustom.aaa
MessageBox("Test:",temp)


执行出错提示：
Application terminated
Error:Error accessing external object property aaa at line 9 in clicked event of object m_open of mainmenu.