Checking non-numbered parts... Checking duplicated references... Checking NoConnection nets for connections... Checking nets with only one connection... ERROR: Net 'GND' is connected to only one pin: CONN1:3 . Checking pins without the 'pintype' attribute... NOTE: Found pins without the 'pintype' attribute: U2:1 U2:2 U2:3 Checking type of pins connected to a net... Checking unconnected pins... Checking slots... Checking duplicated slots... Checking unused slots... No warnings found. Found 1 errors.