PCb123's default minimun trace/space is 0.007". But if your trace's net properties set the space to other bigger number for spacing, you might get DRC "Pad to Pad" error.
This DRC error is because the Net spacing was set to 0.030". To correct this please mouse over Pin 4 's yellow ratsnest line and right click “properties”.
Then change the Spacing to something like 0.007”.