Created Unassigned: unable to add,delete and checkout cart on the server [6]

installed aspcomerrce v 2.0 in server to run an online store..but when i intend to add products to cart and checkout i get a mask background behind that i get a pop message.. unable to click the popup buttion to continue shopping. this issue not occur locally..

This issue due to server permission or css or install version does not support online store?

Plz provide me solution for this issue immediatley as i am on the neck of the project...