I currently have the BB 8520 with 4.6 software, I've been doing to get the O.S 5 update following the 'Upgrade Guide'. I've tried deleting the vendor.xml file but still not luck it still keeps on saying it doesn't have "BlackBerry Device Software". I've tried to following things.

1. Searching my entire computer for another vendor.xml file
2. Re-installing both the upgrade and Desktop Manager

Still no luck, can anybody try and help me out? I've done some searching on the forum and found nothing.


Here are some of my phone specs if it helps

Carrier: Rogers
Phone BlackBerry 8520
OS: 4.6.1.290

Instructions to install, regardless of carrier.

1. Download the above OS file to the PC then install it to the PC by running (double clicking) the file you downloaded.
2. Go to c:\program files\common files\research in motion\apploader and delete the file named "vendor.xml." Vista/Win7 users: In the apploader folder, simply click on "Compatibility files" to see the actual Vendor.xml file. Once you've got that - simply delete the vendor.xml file there (even if you've deleted or think you've deleted it in the folder previously) and voila, it will allow you to update to the newly installed OS!
3. Plug in BB and double click on "Loader.exe." It's located in the same place as the above vendor.xml file.

The process takes about 45 minutes to an hour depending on how much data you have to backup and restore during the process. Once it's done loading the new OS it will reboot (it may do this twice during the entire process.) You will see a white screen with an hourglass for up to 20 minutes at a time while the DM says "waiting for initialization."
If, for some reason, you end up with a white screen with small icons and the number 507, simply connect to the PC again and run Loader.exe again and it should load the OS to the device.

For x64 windows users, it will be located in the above folder with one change: \Program Files (x86)\

orite mate !! i am no blackberry geek !! but i turned into one just last night !!
a simple solution is . download bbsak ( blackberry swiss army knife) software from the net.
2)download the new os u want to install.and install it on ur laptop or pc
3) delete the vendor.xml file
4)open the bbsak software
5)take a backup of ur blackberry using the bb desktop software
6)connect the phone and just press load OS in the bbsak.
Voila!!!
if u got further more doubts or questions PM me.

i had the same problem with my 8520...i tried everything...deleting vendor file, reinstaling desktop manager, tried to load os with BBSAK and still the same...
but then i used option WIPE PHONE on BBSAK...when zou do that, zou will get on screen information on your BB that there is no software instaled...then you click LOAD OS on BBSAK and that's it

first boot will take a while...i was scared that i sc...d something up but eventuali my 8520 started up...

P.S. sorry if my english is bad, i hope that you understud what i was saying

thanks davorthegreat! you were right!!!!