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AR# 33960

Project Navigator - Opening a UCF file results in "Another editor is already editing constraints for this project. ..."


When I attempt to open and edit a User Constraints Format (UCF) file, the following warning appears: 

Another editor is already editing constraints for this project. Running multiple constraint editors (Constraints Editor, PlanAhead, or Text Editor) can result in constraint data being overwritten or not properly updated.

The warning appears when opening the UCF in the ISE text editor, the Constraints Editor, or double clicking the I/O Pin Planning process to open the PlanAhead tool. 

I cannot find another open process or tool that is editing the UCF file. 

Will the UCF file become corrupted? 

How can I avoid this warning message?


Care should always be taken to ensure that a file is not being edited in multiple tools at the same time.  

The situation described above can be caused if the system or the ISE software is shut down while the UCF file is open in the PlanAhead tool. 

When Project Navigator is reopened, attempting to open the UCF in any of the editors results in the error message. 

In this case, the warning message can be ignored.  

To avoid this warning message, delete the PlanAhead_run_# directory in the project directory when PlanAhead is NOT open.

AR# 33960
Date Created 12/15/2009
Last Updated 08/20/2014
Status Active
Type General Article
  • ISE Design Suite - 11.1
  • ISE Design Suite - 12.1