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when i connect my Sony Ericsson K750i to my computer i am unable to access the files on the memory card (or in the phone memory). ubuntu sees it as a 'music player' but there is no way to open it, and on Win7 i cannot install the original support software due to some access violation. anyone knows what i could do about this?

EDIT: when i plug in the phone, i get a new device called /dev/cdc-wdm0 but when i try to mount it, the system just freezes

this forum is 'general ramblings' and it sais non-programming computer questions are ok too

I don't use Linux, but a USB device called "CDC" would indicate communications device class, i.e: a modem.. so it is being exposed as a serial device by the kernel, for tethering and diagnostics.

There are also userland libraries for limited access to the phones filesystem and other features, using libusb and whatnot.

Some devices are multifunction, you may need to look on your actual device for any mention of a USB mass storage mode.

There should be some program named "usb-modeswitch" which could do the job for you...

If it shows up as a "Music player" it probably implements the USB Media Transfer Protocol class. This implements a filesystem over USB abstraction (as opposed to the block device over USB abstraction provided by the Mass Storage Device class).

Windows has a built in MTP driver (XP with Media Player 10+ or Windows Vista or later) if appropriately taught how to interpret the device; the MTP Porting Kit (Which provides an MTP driver for Windows 2000 and earlier) probably contains documentation which will tell you how to activate the driver for your device. You will need the USB VID and PID for this. The Windows MTP driver will not display the device as a drive letter assignment; it will show as a Windows Shell-level device.

Linux does not contain a kernel MTP driver, but there is a userspace implementation in the form of libgphoto2, and there is a GVFS implementation of MTP on top of this (Using the gphoto2:// pseudo-protocol)

If its like my phone (a Nokia N8, when in Nokia Suite mode) both the CDC and MTP functions will be accessible simultaneously.

mariuszp wrote:when i connect my Sony Ericsson K750i to my computer i am unable to access the files on the memory card (or in the phone memory). ubuntu sees it as a 'music player' but there is no way to open it, and on Win7 i cannot install the original support software due to some access violation. anyone knows what i could do about this?

Hello.

When you connect your phone to the computer you have to see a menu appearing on the screen of your mobile. There are two choices in the menu: connect as a phone and connect for file sharing (or something like this, I don't remember how does it say exactly). You must choose the second one. After that you'll have two new flash drives in your computer. When you disconnect the phone from the computer, phone will reboot and you can use it normally. Anyway, it works with my W200i.

Cheers,

Alex