"No net found in footprint error"

Circuit
1

I am getting 40 errors of " No net found in footprint". I created symbol and footprint but it shown error. On schematic editor it works fine. But, in PCB mode it don't show any connection to the board.

2

This could happen, when you assign a footprint with more pads then the symbol has.

Example : If you use the symbol for a 2-pin connector and assign a 2-pin connector with a additional mounting pin(so total 3 pins) you could face this error.