EMP Basefile Edit Help


I need to know how to add an attribute to a basefile section in endpoint manager. This is as close as I have gotten:

   <addOnModule idx="1">
   </addOnModule idx="1">

As you can see, I was trying to add the idx=“1” attribute to the addOnModule section. But it ended up closing with:
</addOnModule idx="1">
that causes an XML parse error on my phone,
I need it to open with:
<addOnModule idx="1">
and close with:

Anyone know how I can do this?
Thank you