Moved to DLP for a faster response.
Removable Storage Protection Rule is in this window :-) This rule do not block MTP-Devices (it control copying files to MTP-devices)
You can block MTP-Devices with Device Control in this :
Thanks for the reply palex
To Block MTP using device rules will I have to know the Device_Id for every make\model I want to block? That's not really workable given all the possible variations.
some contributors suggest that 9.3 natively supports the blocking of MTP devices.
You do not need to enter the type and PID of all the devices to block them.
First, using a DLP find all classes of devices that are in your network (there is a standard request in to the EPO). Then add the tab DLP Policy-Device Management-Device Classes (Windows only) all classes of devices, decide what you will control what is not. For example, attempts to control or lock the entire class of devices, such as controller USB lead to a blue screen of death on computers. Then make Device Definition. Turn back the device class that you want to monitor. Example, New device definition - PnP - USB Class code or Device Class.
After that you need to make the Device rules. Do not forget that if you make a rule to protect, for example, blocking the smartphone, you must include a definition of the devices and to exclude other categories (Include one and Exclude another Device Definitions).