On Fri, 18 Aug 2017, Otared Kavian wrote:

> Hi Aditya,
>
> I tried to typeset your example, but got an error: whether or not the command
> 	% macros=mkvi
> is present on the fist line, then ConTeXt complains saying that
> 	! Illegal parameter number in definition of \MyHeader
> and stops typesetting pointing to the command \stoptexdefinition.

I am attaching the file. It runs fine here with ConTeXt  ver: 2017.08.14 
23:57.

Aditya