Virtualbox fails to mount large FAT32 external drives

[Sylvain Corlay]

Virtual box 4.2.12 with up-to-date extension pack and guest additions fails to mount large FAT32 USB drives (1Tb).

However,

-the same HDD is mounted without any problem when formatted in NTFS -small-sized USB thumbdrives work well (event in FAT32)

Even though FAT32 is not supposed to be used with large drives, it remains the only practical FS for external HDD to be recognized by all common operating systems.

More symptoms: the hard drive shows in USB devices but not in "my computer". After some time, it may appear, but explorer hangs when one tries to open it.

[Sylvain Corlay]

Other people seem to experience this issue: ​http://ubuntuforums.org/archive/index.php/t-1477418.html

[Frank Mehnert]

I don't understand your error description. VirtualBox does not interpret the file system on mass storage devices and VirtualBox does not mount drives. My assumption is that you attached an external USB mass storage device to your Linux host and try to pass this USB device to your Windows guest. That should work if you installed the Extension Pack.

Please attach a VBox.log file of such a VM session.

[Sylvain Corlay]

I am precisely trying to attach a USB mass storage device to my linux host and to pass it to my windows guest. This works perfectly well with other file systems than FAT32.

-> In the case of a (large) FAT32 filesystem, windows will not manage to mount it. It will first not appear in the list of Hard Disk drives. After some time (minutes), the disk will show but cannot be opened in the file explorer.

-> However the device appears checked in the "USB devices" dialog of VirtualBox

-> Unless I release the USB device, the windows guest is unable to launch the "device manager".

-> I am now running Virtual Box 4.3.6 with the latest extension pack and guest additions.

The vbox log file does not show any error.

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.