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From the description and comments it looks like the problem is HW related. I recommend you to do a relay module test (wthout NodeMCU): Try to switch the relays on/off just by connecting the power source you are using for powering the NodeMCU. Connect VCC–5V, GND–GND and one of the IN channels directly to 5V pin. If the relay switches on, try another ...


You seem to compile a sketch from a folder, where more than 1 .ino file is placed. I guess this from the paths, that are mentioned in the error messages. The Arduino IDE supports you to organize your code into multiple .ino files, so that big code can be read way easier. For this it put's together all .ino files in the folder of the main sketch, so that ...

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