Hi, I'd like to connect a Navigon 2110 navigation system to Windows XP running in Parallels Desktop 3.0, Build 5608, host system Mac OS 10.4.11. I set the USB connection properties to let me decide whether a connected device should be connected to the host or to the guest system. After choosing XP, sometimes the drive icon appears in Windows Explorer (after several minutes), sometimes not. Upon clicking on the icon I get the message "E:\ cannot be accessed. The request could not be performed due to an I/O device error." (roughly translated from German). Upon disconnecting the device via the icon in the Windows status bar, the device icon sometimes flashes shortly in Windows Explorer, even if it had not been displayed before. The SD card in the navigation system I'd like to access is possibly NTFS formatted, but I'm not sure about this. Any hints would be appreciated. Best Regards, Jörg
There is no such switch. To avoid miscomprehension: I don't want to use the GPS features via USB (this is not possible with this device, as far as I can tell). I only want to access the SD card. This is needed in order to use the bundled software for updating the maps etc. According to the manual, accessing the SD card through a normal card reader would work as well, but I don't have one. Perhaps I should mention that I managed to mount and to access it once, and I was even able to copy some data. But after awhile the connection got lost. In case you'd suggest mounting in OS X and then sharing the folder to XP: OS X doesn't mount it either. Edit: Another observation: If the drive icon appears in Windows Explorer and I do a "dir e:" on the Windows console I get the error: "Time limit for the semaphore reached" (again, rough translation from German). This has something to do with speed problems while accessing a USB device, hasn't it? Another edit: For whatever reason after connecting and disconnecting the device several times I managed to access it. I tried to use the Navigon software for doing a backup of the SD card. After having copied some 20% or so, Parallels crashed. Report attached.
The issue is most probably due to the fact that MacOS recognizes such devices as USB storage devices and loads a kernel extension which blocks the device. Please note that it is either a MacOS or a USB device limitation, so if the below advice does not work, you should also try addressing the problem to the corresponding manufacturer. So, please, try the following suggestions: - check your device manual and turn it to normal mode if it has a normal/storage modes switch - unplug _all_ USB devices from your Mac (otherwise they will be switched off automatically and it could lead to the data loss). - open Terminal application (Finder -> Applications -> Utilities) - issue the following command: sudo kextunload /System/Library/Extensions/IOUSBMassStorageClass.kext/
Thanks for this hint. That the device is blocked by some OS X process seems plausible. I followed your instructions but ended up with this message: kextunload: unload kext /System/Library/Extensions/IOUSBMassStorageClass.kext/ failed What does it mean that I can't unload this kext? Are there any other kext processes which may be responsible for blocking? I'd like to stress once again that accessing the drive in storage mode is all I need. As far as I can tell from the documentation, concerning the USB connection, the Navigon system should behave just like an ordinary SD card reader or other storage device. As long as I find any way to access the SD card from either OS X or the Windows VM, I am perfectly happy. I will also contact the manufacturer concerning this issue, but I doubt they'll feel responsible for my efforts of accessing their device via a VM...
It means that Mac OS is not able to release USB mass storage kext, it means that it consider GPS device as storage Can you see that SD card in Mac OS, when GPS? if yes you can add it as shred folder to VM
