Anyone know how to write Microsoft Automation AddIn by tB?

[loquat]

1.Using ActiveX template to create project
2.Write a Function like below, and compile an ActiveX DLL
Function MyAdd(Byval a, byval b)
return a+b
end function
3.Open Excel - DevTool - Excel AddIns - Automation, select the AX DLL
error shows: The selected file does not contain a new automation server or does not have sufficient permissions to register on the automation service

[loquat]

Excel automation addin is an ax dll to add user define formula functions which can call in worksheet.
which is different from VBA VBE addin as well as Com AddIn
for example: write in Range A3
=MyAdd(A1,A2)