Problem Description: 

I am  unable to edit/modify any element by Modify Properties dialog or from the Schedules dialog How can I resolve this issue?

Resolution: 

1. When you are unable to modify any elements the first thing, to check is the DataGroup instance name assigned to that element is present in the active Open Buildings Designer configuration. If not, then you will need to reassign the DataGroup instance data to one  which is available in the OpenBuildings Designer configuration or determine why the applied instance data is missing from the configuration. .
   
   
   
   
   
   2. If the DataGroup instance is already available but you are still unable to edit/modify then select that element and go to its Properties dialog and confirm in the Extended Tab whether the element is Locked or Unlocked.
   
   
   
   On the above image we can see that as the element is Locked, then we will not be able to edit that. Try to unlock the element by clicking on the dropdown and changed the option to Unlocked.
   
   
   
   once you have changed the element status to Unlocked, you sould be able to modify that element.
   
   
2. There can be another instance where the level of that element is locked and at those times, the element modification is not possible.
   
   
   
   

   In the above image you can see that the Level associated with the element is locked, so clicking on the lock icon will make the level unlocked. Once it is unlocked, you should be able to perform modification.
   
   

So, to resolve this issue, please properly check all of the above three steps.