Description

1. PAR is canceled, fails or completes with zero Errors, but the flow stops in PlanAhead due to the design failing to route with a warning, WARNING:PAR:100.
   "PAR ERROR" is returned on Design Runs.
   Because implementation does not complete, I cannot open the Implemented Design to debug the partial placement.
    
2. I have a partial or fully routed .ncd file created outside of PlanAhead.
   Is there a way to open this .ncd file in PlanAhead for analysis?

Solution

1. Open the Netlist Design. 
    
   The Import Placement option in step 2 will not be available without an active netlist open.
    
2. Select File -> Import -> Import Placement.
    
3. Browse and select the desired .ncd file.
    

For an .ncd file generated outside of PlanAhead, create a new project and use the Import Place & Route results option in the New Project Wizard.

1. Select File -> New Project in the PlanAhead GUI.
    
2. Click Next on the first page of the New Project Wizard.
    
3. Choose a project name and location and click Next.
    
4. Select Import ISE Place & Route results.
    
5. Continue through the wizard to create the project.