Can't access ZoHo mail setup

Can't access ZoHo mail setup

Hi, I am a top level user on our ZoHo system and want to activate and configure ZoHo mail add-on.  Another colleague with exactly the same access rights can click on the big green 'Configure Now' button and gets to the config page - I do it and literally nothing happens.  I've tried in Chrome and Firefox and IE!

I get a small 'loading' yellow notification at the top of the page for a second then that goes. Sometimes I get a popup box with 'unable to process your request' if i click several time on the button....

As I am the administrator of the system I need access to this function.

Anyone else had this?