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I tapped download and install manually option in Windows Phone store and I downloaded an xap file. I transferred the xap file to my Lumia 435 via bluetooth, but the OS does not install it, displaying "Cannot install company app..." I checked out This Microsoft Thread on how to install xap files. It says, "Tap more option on apps list and then tap install local apps (or SD card)." I don't see any such option in my apps list.