"Conversion failed" error when opening Project treeview

SYMPTOMS:

Search on the Project treeview returns following error

ERROR:

Server Error in '/' Application.

Conversion failed when converting from a character string to uniqueidentifier.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Stack Trace:
... Changepoint.Enterprise.Treeview.tvProject.CreateProjectNodes()...
 

REASON:

Upon incomplete save to create tasks using project worksheet, 'Tasks' table produces NULL and blank data for treeview order. 'WBS' and 'OBS' values will be displayed as NULL and empty.

RESOLUTION:

Run WBS utility for appropriate Changepoint version