My Nexus 4 always recognised as ADB device instead of MTP I plugged in Nexus 4 to my windows machine(XP Service Pack 2) and it didnt recognise or install any software automatically. I downloaded some ADB drivers from google and now it shows up as recognised device(that is ADB device) in the Device Manager, but it is not recognized as MTP . because of this i am not able to tranfer data into my phone or vice versa...
Uninstall the device from Device Manager, then plug it out and in again :)