Off-path???

Lately, I've been exploring new-to-me scenarios from the West Sommerset RR route, many of which involve my preferred type of task: shunting. One of these, titled "Finishing Up", eventually led to a peculiar error message, "Denied. Your train appears to be off path" (see screenshot below), which was accompanied by a red signal 40 yards ahead warning.
Having saved the scenario following completion of the previous instruction, I dropped out of the scenario and immediately resumed it from the save I'd made just before this Stop at Location instruction. The same error cropped up again!
I'd like to hear from anyone who has experienced this same error, especially anyone who has found a way around it.

Thanks!

 

This message usually signals that you are no longer on the scenario path, most likely having failed to set the manual switches properly.
I usually check the path (marked green in the interactive map) and make sure the switches are correctly set.
Sometimes it's possible to reverse for a bit, to get back on the correct path. Other times, signals will make that impossible, and you must restart the scenario.

 

Thanks for replying, but I already know all of that and tried all of that. However, a fresh run of the scenario the next day did not get stuck at this point. Who knows why?

 

check the 2d map first!