I'm having these errors, it's working!
I've added the reference, the BLL folder is right along the way. I've tried and researched everything but I do not understand what I have to do. I have re-created the project 3 times and can not get this error to compile.
Andnowyou'regivingthistoo:
What could you do to resolve this?
The first error refers to the version of the framework used, it is warning that npgsql requires .net 4.5.1 and you are using 4.5. in your solution, go to properties and change the framework used.
The second error is that you can not start the program through a DLL, you must define an application as the initial project. Right-click GUI, then 'Set as startup project'
I can not understand your question well, the image you published with the error, is not visible to send another image?
But test this: go to "soluntion explore" with the cursor over the name of the project click on the sub menu of the mouse (mose) goes to property and select the "Set as sartup Project" option if it does not result does the following, where Debung replaces with Release.
