The Error List
The Error List displays error messages generated during the build process.
The Error List is shown at the end of the build process if there are errors generated during the build process.
Each error has a type (Error, Warning, Message)
For errors derived from a specific object definition, you can go to the object with the error by double clicking on the error message.
There is a description of the validation that can generate errors in the build process in the section Validation in the Build Process.