For the best results, do not use Desktop Manager to upgrade. use AppLoader instead.
on your pc click the start menu>My computer>C: Drive>Program files>common files>Research in Motion>AppLoader
Remember to delete the Vendor.xml file before you proceed.
Also, to initiate the AppLoader program, it's the icon that looks like a phone. It's like 9,270 KB in size. You should click that once you delete the vendor file and have your phone connected.
If Desktop Manager pops up when you plug in your phone, simply close that program before doing the above steps