Serial port not found

Hello,

I was actually working with my Arduino in the morning and I remember using a metal plate as base. Since then, I'm having trouble connecting to my Arduino over Serial. I tried to connect to it on both Windows and Linux but it looks like the 'Tools > Serial Port' menu doesn't list any.

Thank you in advance for any kind of help!

Try loopback test.

Well in order to perform loopback test I need Serial Monitor, but I can't access serial monitor since my Arduino is not detected by the IDE.