In certain cases, the property builder totally corrupts your windows form and makes the Rad grid unsable, undeletable and un-editable . It happens If you inadvertently click "Open Property Builder" on a RadGridView while your project is running (yes, sometimes you forget it is running and still have the form designer window open), if you try and make some changes to the MasterTemplate and click "Ok" it renames your grid to "MasterTemplate" and makes it unsable, even while your program is running.
The grid then becomes corrupt and you cant delete it or fix it.
Test it by starting a new VB winforms project in VS2015, drag a radgrid onto the form, run the exe in VS and then click on property builder on the rad grid. make a few changes to master template and click ok.
Your form will now be unrecoverably corrupt.