When Pex does not achieve high code coverage, it might be that the instrumentation is not set up correctly and a lot of methods do not get instrumented. As a result, Pex does not 'know about' the things that occur in those method and cannot generate relevant inputs.
The reports provide detailed information about executed methods that were not instrumented by Pex. The user should use the reports to troubleshoot instrumentation problems.
Uninstrumented Call Menu
The uninstrumented call menu will be displayed if uninstrumented calls occur, at the assembly, fixture and exploration level in the reports. Click to open/close the table.
Uninstrumented Call Table
The uninstrumented table displays the full list of uninstrumented managed methods.