Two android (nexus 4, and nexus 10) devices with cyanogenmod (nightly) are connected to windows 7. When the nexus 4 is connected windows shows it in explorer and it is possible to transfer files to/from it though MTP. Attach the nexus 10 and nothing appears, unless MTP is deselected (under storage) and PTP is selected. Then it is possible to transfer files to/from, yet only from the "Pictures" folder of /data.
Further information android sdk is installed and the google usb drivers have been loaded for both devices. ADB recognizes the nexus 4 but not the nexus 10 unless the nexus 10 is put into PTP mode.
How can this be explained?