What is causing my connection to my sql server not to connect?

My bartering app that reads from a sql server database freezes at connection_1.open .[[[[enter image description here](
https://i.stack.imgur.com/oPKGp.png)](https://i.stack.imgur.com/1xvaS.png)](https://i.stack.imgur.com/h3Izl.png)](https://i.stack.imgur.com/tvPNA.png) />

I was expecting the connection to go through.


What causes the above error?


Please help