I've got a 9860 that kept restarting ( no idea what vendor) so i downloaded the OS for at&t.I wiped the phone with bbsak and when i hit load os it says no os found.So i opened apploader and ran it.It more or less said the os i downloaded wasn't compatible so i went to look for the os i downloaded to delete the vendor file and i cant find the vendor file to delete it.I know it's here some where .HELLLLLLP
You can also use the search function in your computer. Search the entire drive where you install your blackberry os. Sometimes there are 2 vendor.xml files.