Unable to get property 'style' of undefined or null reference

[edgarvzla78]

Hi!,
The shadowbox is not showing due it is getting the next error when It arrives to the line (shadowbox.js) :
aa.style,display="block";

the error is:
Unable to get property 'style' of undefined or null reference

I am trying to open the PHP page which is using the shadowbox.js library and javascript code to open the shadowbox, Opening from a .Net web page through an iframe object (assigning the Url of the php page) ...

It is properly working when opening the PHP page directly but it is not when opening from the .net web page through an iframe.

Please help...