title: ADB doesn't find android tablet Trekstor SurfTab Ventos 7.0 HD
body: <p>As the title says, I'm trying to connect the android tablet "Trekstor Ventos 7.0 HD" per USB to my PC (running Win7 Professional), but it doesn't get recognized by ADB. I'm aware of the steps which are supposed to work, but they don't. So let me describe in detail what I already tried:</p>
  
  <p>From the vendor's site: <a href="http://www.trekstor.de/product-support/product/surftab-ventos-70hd.html#faq154" rel="nofollow">http://www.trekstor.de/product-support/product/surftab-ventos-70hd.html#faq154</a></p>
  
  <blockquote>
    <p>Firstly, make sure that the USB debugging mode is activated in the SurfTab developer options. If the developer options are not displayed, go to "Settings" -> "About Tablet" and tap "Build number" until "Developer options" appears under "System". Ensure that you have already installed and configured the latest Android SDK.</p>
    
    <p>For Windows:
    Go to the Windows device manager and check whether there is a device marked with a yellow exclamation mark (!) that corresponds to your tablet. Right click this entry and select "Properties". In the "Driver" tab, click "Update driver's software". In the window that follows, select the option "Browse my computer for driver software" and enter the path where the unzipped TrekStor "android_winusb" driver is located. If you receive a message during installation that prompts you to not install this driver, confirm with "Install this driver software".</p>
    
    <p>Windows and MAC OS X:
    It is now necessary to configure the ADB for the TrekStor tablet. You must add the TrekStor Vendor-ID (0x1e68) to the "adb_usb.ini" file in the hidden ".android" folder. To do so, proceed as follows:</p>
    
    <p>Windows:
    1. Open the command prompt and enter the command "echo 0x1e68 >> $HOME/.android/adb_usb.ini".
    2. Now check whether the device has been recognised by opening "cmd.exe" and entering the commands "adb kill-server" and "adb devices" in succession.</p>
  </blockquote>
  
  <p>So... I did all that, and ADB doesn't show any connected devices. I think the problem is caused by the USB driver(s), but I don't know how to fix it. When I connected the tablet for the first time, Windows automatically installed drivers which allow to access the tablet's storage. In the device manager, the tablet shows with a couple entries: 1 main node "Portable Devices" with 2 subnodes "I:", "J:" for the internal and external SD card. Under "Disk Drives" there are 2 nodes "SurfTab ST70216-1 USB Device". And under "Universal Serial Bus Controllers" there's a generic node "USB Mass Storage Device".</p>
  
  <p>Trying to manually upgrade the drivers for the portable devices or disk drives doesn't work, Windows insists that the best driver is already used.</p>
  
  <p>Trying to upgrade the driver for the "USB Mass Storage Device" <em>does</em> have some effect, just not the desired one: Windows installs an Android driver, and after that only 1 Android device shows in the device manager. But ADB still doesn't see any devices. Furthermore, all other entries (for the storage stuff) vanish, and it's impossible to access the SD cards anymore. So I undid that, but I have the feeling that I was on the right track there.</p>
  
  <p>Does anybody have an idea what else to try?</p>
  
  <p>--
  Edit: As Alex P. suggested, I tried the following powershell commands:</p>
  
  <blockquote>
    <p>powershell "gwmi Win32_USBControllerDevice | %{wmi} | ?{$_.CompatibleID -like \"USB\Class_ff^&amp;SubClass_42^&amp;Prot_0?\"} | %{write \"0x$([regex]::match($<em>.deviceid.tolower(), 'vid</em>(\w+)').groups[1].value)\"} | sort -u" >> %USERPROFILE%.android\adb_usb.ini</p>
  </blockquote>
  
  <p>This gave no result, meaning no entries got added to adb_usb.ini
  So I checked the whole list, before filtering it with the regular expressions:</p>
  
  <blockquote>
    <p>powershell "gwmi Win32_USBControllerDevice | %{wmi} >> usb.txt</p>
  </blockquote>
  
  <p>By comparing the results with and without connecting the tablet, here are the entries which get added when the tablet is connected (mass storage mode, usb debugging enabled):</p>
  
  <pre><code>__GENUS                     : 2
  __CLASS                     : Win32_PnPEntity
  __SUPERCLASS                : CIM_LogicalDevice
  __DYNASTY                   : CIM_ManagedSystemElement
  __RELPATH                   : Win32_PnPEntity.DeviceID="USB\\VID_1E68&amp;PID_0074\
                                \253C99D78F6045BB425BBCF0C7D3939D"
  __PROPERTY_COUNT            : 24
  __DERIVATION                : {CIM_LogicalDevice, CIM_LogicalElement, CIM_Manag
                                edSystemElement}
  __SERVER                    : ROBERT-PC
  __NAMESPACE                 : root\cimv2
  __PATH                      : \\ROBERT-PC\root\cimv2:Win32_PnPEntity.DeviceID="
                                USB\\VID_1E68&amp;PID_0074\\253C99D78F6045BB425BBCF0C
                                7D3939D"
  Availability                : 
  Caption                     : USB Mass Storage Device
  ClassGuid                   : {36fc9e60-c465-11cf-8056-444553540000}
  CompatibleID                : {IUSB3\DevClass_00&amp;SubClass_00&amp;Prot_00, IUSB3\Dev
                                Class_00&amp;SubClass_00, IUSB3\DevClass_00, IUSB3\CO
                                MPOSITE...}
  ConfigManagerErrorCode      : 0
  ConfigManagerUserConfig     : False
  CreationClassName           : Win32_PnPEntity
  Description                 : USB Mass Storage Device
  DeviceID                    : USB\VID_1E68&amp;PID_0074\253C99D78F6045BB425BBCF0C7D
                                3939D
  ErrorCleared                : 
  ErrorDescription            : 
  HardwareID                  : {USB\VID_1E68&amp;PID_0074&amp;REV_0231, USB\VID_1E68&amp;PID
                                _0074}
  InstallDate                 : 
  LastErrorCode               : 
  Manufacturer                : Compatible USB storage device
  Name                        : USB Mass Storage Device
  PNPDeviceID                 : USB\VID_1E68&amp;PID_0074\253C99D78F6045BB425BBCF0C7D
                                3939D
  PowerManagementCapabilities : 
  PowerManagementSupported    : 
  Service                     : USBSTOR
  Status                      : OK
  StatusInfo                  : 
  SystemCreationClassName     : Win32_ComputerSystem
  SystemName                  : ROBERT-PC
  
  __GENUS                     : 2
  __CLASS                     : Win32_PnPEntity
  __SUPERCLASS                : CIM_LogicalDevice
  __DYNASTY                   : CIM_ManagedSystemElement
  __RELPATH                   : Win32_PnPEntity.DeviceID="USBSTOR\\DISK&amp;VEN_SURFT
                                AB&amp;PROD_ST70216-1&amp;REV_DF84\\253C99D78F6045BB425BB
                                CF0C7D3939D&amp;0"
  __PROPERTY_COUNT            : 24
  __DERIVATION                : {CIM_LogicalDevice, CIM_LogicalElement, CIM_Manag
                                edSystemElement}
  __SERVER                    : ROBERT-PC
  __NAMESPACE                 : root\cimv2
  __PATH                      : \\ROBERT-PC\root\cimv2:Win32_PnPEntity.DeviceID="
                                USBSTOR\\DISK&amp;VEN_SURFTAB&amp;PROD_ST70216-1&amp;REV_DF84
                                \\253C99D78F6045BB425BBCF0C7D3939D&amp;0"
  Availability                : 
  Caption                     : SurfTab ST70216-1 USB Device
  ClassGuid                   : {4d36e967-e325-11ce-bfc1-08002be10318}
  CompatibleID                : {USBSTOR\Disk, USBSTOR\RAW}
  ConfigManagerErrorCode      : 0
  ConfigManagerUserConfig     : False
  CreationClassName           : Win32_PnPEntity
  Description                 : Disk drive
  DeviceID                    : USBSTOR\DISK&amp;VEN_SURFTAB&amp;PROD_ST70216-1&amp;REV_DF84\
                                253C99D78F6045BB425BBCF0C7D3939D&amp;0
  ErrorCleared                : 
  ErrorDescription            : 
  HardwareID                  : {USBSTOR\DiskSurfTab_ST70216-1_______df84, USBSTO
                                R\DiskSurfTab_ST70216-1_______, USBSTOR\DiskSurfT
                                ab_, USBSTOR\SurfTab_ST70216-1_______d...}
  InstallDate                 : 
  LastErrorCode               : 
  Manufacturer                : (Standard disk drives)
  Name                        : SurfTab ST70216-1 USB Device
  PNPDeviceID                 : USBSTOR\DISK&amp;VEN_SURFTAB&amp;PROD_ST70216-1&amp;REV_DF84\
                                253C99D78F6045BB425BBCF0C7D3939D&amp;0
  PowerManagementCapabilities : 
  PowerManagementSupported    : 
  Service                     : disk
  Status                      : OK
  StatusInfo                  : 
  SystemCreationClassName     : Win32_ComputerSystem
  SystemName                  : ROBERT-PC
  
  __GENUS                     : 2
  __CLASS                     : Win32_PnPEntity
  __SUPERCLASS                : CIM_LogicalDevice
  __DYNASTY                   : CIM_ManagedSystemElement
  __RELPATH                   : Win32_PnPEntity.DeviceID="USBSTOR\\DISK&amp;VEN_SURFT
                                AB&amp;PROD_ST70216-1&amp;REV_DF84\\253C99D78F6045BB425BB
                                CF0C7D3939D&amp;1"
  __PROPERTY_COUNT            : 24
  __DERIVATION                : {CIM_LogicalDevice, CIM_LogicalElement, CIM_Manag
                                edSystemElement}
  __SERVER                    : ROBERT-PC
  __NAMESPACE                 : root\cimv2
  __PATH                      : \\ROBERT-PC\root\cimv2:Win32_PnPEntity.DeviceID="
                                USBSTOR\\DISK&amp;VEN_SURFTAB&amp;PROD_ST70216-1&amp;REV_DF84
                                \\253C99D78F6045BB425BBCF0C7D3939D&amp;1"
  Availability                : 
  Caption                     : SurfTab ST70216-1 USB Device
  ClassGuid                   : {4d36e967-e325-11ce-bfc1-08002be10318}
  CompatibleID                : {USBSTOR\Disk, USBSTOR\RAW}
  ConfigManagerErrorCode      : 0
  ConfigManagerUserConfig     : False
  CreationClassName           : Win32_PnPEntity
  Description                 : Disk drive
  DeviceID                    : USBSTOR\DISK&amp;VEN_SURFTAB&amp;PROD_ST70216-1&amp;REV_DF84\
                                253C99D78F6045BB425BBCF0C7D3939D&amp;1
  ErrorCleared                : 
  ErrorDescription            : 
  HardwareID                  : {USBSTOR\DiskSurfTab_ST70216-1_______df84, USBSTO
                                R\DiskSurfTab_ST70216-1_______, USBSTOR\DiskSurfT
                                ab_, USBSTOR\SurfTab_ST70216-1_______d...}
  InstallDate                 : 
  LastErrorCode               : 
  Manufacturer                : (Standard disk drives)
  Name                        : SurfTab ST70216-1 USB Device
  PNPDeviceID                 : USBSTOR\DISK&amp;VEN_SURFTAB&amp;PROD_ST70216-1&amp;REV_DF84\
                                253C99D78F6045BB425BBCF0C7D3939D&amp;1
  PowerManagementCapabilities : 
  PowerManagementSupported    : 
  Service                     : disk
  Status                      : OK
  StatusInfo                  : 
  SystemCreationClassName     : Win32_ComputerSystem
  SystemName                  : ROBERT-PC
  </code></pre>
  
  <p>So... it's relatively obvious why the regular expression doesn't find the tablet; the CompatibleID string doesn't look like expected. Does this mean the tablet doesn't expose an ADB interface in mass storage mode? What could I do about that? It's running Android 4.1 and doesn't offer MTP or PTP modes for usb connections at all...</p>
  
  <p>--
  Edit 2: It's probably not much help, but I took screenshots of the settings screen, to show that I can't switch to MTP/PTP there: <a href="http://imagizer.imageshack.us/a/img537/6923/CQ8VET.png" rel="nofollow">http://imagizer.imageshack.us/a/img537/6923/CQ8VET.png</a></p>