Can't delete Categories

HI, I've instaled cosmetics by hotstart, trying to delete all demo categories and I get an error al the time - "Could not clear category products" I cant move them ether. I have deleted all products from them. On forums people giving advice to clean trash in joomla - but I have Joomla 1,7.3 and VM2 and it doesn't have trash as it was in previous versions.
Thank you !

You have "Empty Trash" option in article and category manager when you select filter Select Status to "Trashed"