i am using 9.5. for u i giving one more solution verify it.

Dim oDesc
Set oDesc=Description.Create()
oDesc("micclass").value="WinEdit"
iObjCount=0
For iIndex=0 To 100
If Dialog("regexpwndtitle:=Login").WinEdit
(oDesc,"index:="&iIndex).Exist(2) Then
iObjCount=iObjCount+1
Else
 Exit For
End If
Next
msgbox iObjCount
  
iObjCount gives editboxes count. u can keep what ever value 
u want for ending of for loop.But it must be greater than 
equal value,then only u can get correct number.