Thumbnails Images Not Showing Up

Greetings! I am a longtime Joomla user and finally decided to jump ship to WordPress. So I am familiar with CMS but a total WP noob. I set this up on my server and as far as I can see everything else is going just fine except one stubborn issue:

On a website that I setup for a friend ( tech-chatter.com )none of the images on the main pages show (they do show up in the article). I see from the source code that where the images should be is: img src=””

I HAVE NO idea where I would need to go to set this correctly. The images DO appear inthe article and I see them on the server (I havs shell access)

The missing images occur on all templates installed

Thanks you in advance!