Thank you Daniel! This has been driving me nuts for awhile now. I have the team provide me updates referencing the project version number and line number. It was torture trying to update when the numbers kept disappearing.
Add an Indicators column on the left and make it larger than the indicator information. Hoover the curser to the left of the indicators column and when it changes to the + drag that to the right and the line numbers will reappear.
One option might be to add a different column as the first column of the table and re-select the Lock first column checkbox. Maybe the WBS if you aren’t using it or a blank task custom field. Then sort by ID as the second column.
I don’t have the problem you are all facing so I don’t have any other thoughts. Hope that helps…
Daniel’s solution does work for the disappearing (randomly appearing) ID numbers. Unfortunately with it set this way I am unable to grab and move a task within the plan. So for now I Lock the column, move tasks around as needed, then unlock it again to see my ID numbers.