I have a 200 el lw 17 with some analog trunks not in use. when I try to delete a trunk (say bay 2, slot 1, circuit 1) I get a major alarm and a log entry (major alarm due to trunk deleted). very odd.

the trunk is not in a trunk group and not in use. there is trunk card in the slot. perhaps I am missing something.

Is it assigned to a key on a phone maybe?

it is not on any phones. I checked. thank you for that idea!

the log entry is " alarm level changed to MAJOR due to trunk in bay 1" so maybe I have something screwy in my alarm level settings. I would think deleting a trunk would not affect alarm levels, maybe just busy-ing it out.

I think you hit it on the head. If you have say, 4 trunks and you take 1 out of service, 25% of the lines are down. Definitely check alarm thresholds for the lines, and set them higher.