Diagnosis
After you have edited this object with the appropriate tool you will beable to adust it using the Modification Assistant.

System Response
The object is still displayed in the category "without ModificationAssistant" in the tree.

Procedure
Update your display. The object should be deleted from the "withoutModification Assistant" category in the tree and inserted in thecategory "with Modification Assistant" where you can now process itnormally.