debugging - debug wpf by using sos.dll issue -

I am using sos.dll to find memory leak in wpf. And I think a WPF object was not released, then I tried to know that it ! Why did not I quit using Gcroot

, he gave me warming:

Please note that 6c369950 is not a valid object is.

Snippet of debugging info

 ! Dumphepe-type WPFUILib.MenuWindow Statistics: MT Count Total Category Category Name 0c12ef4c 14 224 WPFUILib.MenuWindow + & lt; & Gt; C__DisplayClass2b 03fdf624 2 816 WPFUILib.MenuWindow Total 16 Objects! Gcroot 03fdf624 Note: The found roots on the heap can be false positives. For more information, run "Help gcroot"! Please note that 03fdf624 is not a valid object. You are trying to find roots for MethodTable (MT), but  

! Gcroot is expecting an object address if you want to find the roots of two examples of WPFUILib.MenuWindow , then you must first locate your address. to list the address! Use Dumpheap -mt 03fdf624 and then use gcroot on them