Courtesy of The Revit Clinic
Purge Imported Categories
At some point or another you've probably had some leftover imported categories in a Revit project and couldn't seem to delete them.
In most cases you can remove these using Manage > Purge Unused, or by deleting the last instance of the import in the project. However if a detail or model group is using an import instance you will be unable to purge the instance from the project.
If some imported categories remain and they don't appear to be in use, check the project for the following:
1. Under Project Browser > Groups > verify if the project contains any detail or model groups.
2. If so you can expand to highlight a group > right-click > Select all Instances > In Entire Project. Then temporarily delete the group instance[s] > Manage > Purge Unused.
3. See if the import instance now appears under Families > <Import Instance Name>.
If not you can undo and test selecting \ deleting another group to isolate which one may contain the import instance.
In most cases you can remove these using Manage > Purge Unused, or by deleting the last instance of the import in the project. However if a detail or model group is using an import instance you will be unable to purge the instance from the project.
If some imported categories remain and they don't appear to be in use, check the project for the following:
1. Under Project Browser > Groups > verify if the project contains any detail or model groups.
2. If so you can expand to highlight a group > right-click > Select all Instances > In Entire Project. Then temporarily delete the group instance[s] > Manage > Purge Unused.
3. See if the import instance now appears under Families > <Import Instance Name>.
If not you can undo and test selecting \ deleting another group to isolate which one may contain the import instance.
