install signal / update error

[DeepThought]

Not sure how you typed this part into terminal but it should be one line

Code:

echo "deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main" | sudo tee -a /etc/apt/sources.list.d/signal-xenial.list

To check the sources list:

Code:

sudo nano /etc/apt/sources.list.d/signal-xenial.list

The only line in the signal-xenial.list file should be

Code:

deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main

You may need to edit the line, then control-x , y, and enter to save any edits.
Then try:

Code:

sudo apt update && sudo apt install signal-desktop