The "excessive opening force detected", means exactly that, it is taking too much power to get the door to open or move.
This is normally due to spring failure or weakness, since the springs do all the work, not the opener.
What type of door is this?
Any garage door should open with minimal work, one hand on the door hadle and one to apply a small amount of extra pressure and the door should swing open after a fot off the ground with no force needed or else an electric opener cannot open the door.
The springs do all the work, not the opener.
The opener is basically a guide to control the door and take it to open and close with minimal force.
Where are your springs, on the sides or above the door?
Get a picture of them for evaluation if possible.