Windows form displaying error on design, could not find '.config' file with no filename

Question

Visual Studio Project consists of a Windows Form and a Console application project it calls on a button click event. Main Form has multiple User Controls that are brought to the front for user access. After some recent changes adding in the call to the console app, attempting to open the main for gets me the error:

The file it is referencing does not exist, and is not referenced in either projects .csproj files.

What could have caused this to occur?

Answer 1

This was caused by an on Load method in a User control in the main Form. The Load method attempted to retrieve values from the app.config file, and did not check for Design Time.

Adding a check to see if in DesignMode to the on Load method resolved this issue.

if(!DesignMode)
            {
                methodWithConfigLookup();
            }