If you are referring to assets listed in the Undefined section of the IP location overview: if an asset doesn’t belong to any IP location you’ve created, it is automatically added to the built-in Undefined group. This group cannot be renamed or deleted.
If you add your assets to an IP location of your own, under Configuration/Website Management/Asset Groups, they will automatically disappear from the Undefined group. More info on IP locations can be found on page 118 and beyond of our online documentation: http://www.lansweeper.com/documentation.pdf
Note that we use the page numbers listed at the bottom of each page.