Here are some nets in a schematic. At first sight they look OK.   Now run the Design Manager, refresh the Nets view and see that there are problems on the FB2 and PP nets. What could be wrong? Click on each net to see that the wires are not exactly on grid so, as the warning at the bottom of the Design Manager panel shows, the net label is not correctly attached. This will cause problems when subsequently attempting to route the PCB.   Correct the misalignment, refresh the Nets view in the Design Manager and the errors are cleared!