ID:169016 Cannot place I/O pin <name> in VREF pin location <name> -- the specified VREF pin location is used as VREF by other pins in the same I/O bank

CAUSE: You assigned the specified I/O pin to the specified VREF pin location in the device. However, the Fitter cannot place the pin in the location because the specified VREF pin location is being used as VREF by other pins in the same I/O bank.

ACTION: Assign the I/O pin to a different location.