How to fix when you are trying to edit a level in Level Manager in your sheet model, but all the levels are greyed out? Please refer to the screengrab below.
When you are trying to edit any levels in the Level Manager in your sheet model, but it is showing as greyed out then open the Configuration Variables dialog box and search for this variable “MS_LEVEL_DO_NOT_OVERRIDE_DESIGN_LEVELS_IN_SHEET”. If the value of this variable is set to 1 then you will not be able to edit any levels in the sheet/drawing model. Then simply delete that value and save the config variable. After that you can see that you are able to edit any levels in your drawing/sheet model. Please refer to the screengrabs below.