Can't add an item to a cart

[Littlepants]

I think this may possibly be group related, so firstly can products be added available to a specific group only, and how can this be changed? 

If not can anyone explain why a specific product cannot be added to a cart when other items can? When logged in as a customer, and I click the add to cart button, nothing happens. The item is not added to the cart.

Version 1.7.6.8

[PrestaServicePro]

Hi,
Could you please provide us with more info? We need more details to understand how we can reproduce your issue:

server setup and configuration

debug mode report

PHP error logs

javascript console log

screenshots

[Littlepants]

I have no idea what all this means! 

I have temporarily solved the current issue by making a new product and disabling the old one. I just want to know if it's possible to make a product available to a specific group only, and how to do or change that.