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I had a schematic, then I went to do layout work in Pcbnew.

I layed out the parts and then proceeded to draw the easy traces, the low hanging fruit.

This is the PCB at this point:

enter image description here

I had created a GND layer in the bottom side copper.

However, since I had 3 ICs that all used 5V power, I decided to duplicate the bottom layer to the front side copper and have it at 5V, instead of GND.

To give them the proper value, I wanted to have a label, so it is easy to find it.

I went ahead in the schematic editor and added the label Vdd.

enter image description here

Then I pressed "Update PCB from schematic."

enter image description here

Unfortunately, I now get two errors about two of the button's pads.

I don't understand why I get those errors because I did not mess around with the button at all.

enter image description here

How come there was no error the first time, and now I have an error about the button, while I changed nothing on the button?

I cannot debug this at all and unfortunately, I cannot procceed with my design.

EDIT: Here is my schematic picture of the switch I used (4 pins.):

enter image description here

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The error is saying that your sw1 in your schematic has 4 pins (named 1, 2, 3, 4), but the footprint connected to that switch only has 2 distinct pads (only 1 and 2, could be spread out to more pads with the same name). Thus it cannot connect the two nets that are left. Try editing the footprint association, footprint or schematic so that it reflects your real-world design. (And make sure the footprint has the same amount of pins/pads as the symbol in your schematics.)

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  • \$\begingroup\$ This footprint has 4 actual pads, two of them are named (1) and the other two are named (2). I mean 4 pads, but in reality, 2 different signals. But why did it work the first time? \$\endgroup\$ Dec 25, 2020 at 23:08
  • \$\begingroup\$ @user1584421 not sure why it worked, but I edited my answer to reflect why it failed; the footprint pads are not given the same name. (1...4) so pins 3&4 in your schematic have no idea what pad to connect to. Try editing the footprint and rename two corresponding pads to 3&4. Be sure to get the connections right. (A tactile switch often has two pins shorted together, in that case I would edit the schematics symbol to remove two “useless” pins. \$\endgroup\$
    – Ananas_hoi
    Dec 25, 2020 at 23:11
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    \$\begingroup\$ Thanks! I edited the question with a picture of the schematic symbol i used. Since this is my first pcb design project, and all the schematic symbols and footprints were found with a lot of effort, do you happen to know which schematic symbol should i use for the pushbutton that has 4 pads, but only 2 are the actual ones? \$\endgroup\$ Dec 25, 2020 at 23:20
  • \$\begingroup\$ @user1584421 so in essence you are saying that it’s a switch with 4 pins and 2x2 pins are always connected, and the pairs (dis) connect when you press the switch? If it’s a momentary switch, just use the simpelest button symbol with 2 pins. (Or the normal closed version) edit: can you provide the datasheet/product page of the switch you are planning to use? \$\endgroup\$
    – Ananas_hoi
    Dec 25, 2020 at 23:23
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    \$\begingroup\$ Thank you sir! Merry Christmas by the way! \$\endgroup\$ Dec 25, 2020 at 23:37

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