Access Denied to Use Templates

I am trying to create a new site using a custom template. I am the new admin here at the company. Other also are having "access denied" errors when trying to create the site using these custom templates. 

However I can still create a site using the out of the box templates. I have given myself site collection admin (primary) and I am a farm administrator as well. Any ideas on why I keep getting access denied to specific templates?

Thanks!