Click on the "Database" tab from the main ribbon and select Element Management -> Delete within the "furnishings" section (as shown below).
In the window that appears, select the manufacturer that you would like to eliminate from the archive and leave the value "All" in the Destination and Typology fields.
Confirm the operation by clicking Ok.
In the next window, a list of all the items from the selected manufacturer will appear.
If you want to eliminate all of these items, click the Select All button and confirm the operation by clicking Ok. In the next window that appears, again click the Select All button.
If you only want to eliminate certain items from the selected manufacturer, select the items you want to eliminate from the full list (select multiple items with the CTRL key). Confirm the operation by clicking Ok.
This article is valid for the 2017 version and later.