VirtualBox: Failed to access the USB subsystem

To fix this error, just add the user name to the "vboxusers" group but the User Accounts manager in Ubuntu 11.10 is quite terrible, too simple to be useful so use a command line to do this instead:-

sudo usermod -a -G vboxusers <user-name>

The other option is to install and run the old Accounts manager.

sudo apt-get install gnome-system-tools
users-admin

Refs
http://www.liberiangeek.net/2011/10/add-users-to-existing-groups-in-ubuntu-11-10-oneiric-ocelot-2/
http://linux-software-news-tutorials.blogspot.com/2011/11/restore-old-account-manager-in-ubuntu.html

vReplicator fails with the message: - " 'Consolidate Helper' snapshot found"

VMWare ESX/ESXi creates a temporary snapshot called "Consolidated Helper" during the snapshot deletion/consolidation. It should be deleted automatically but if it's left behind (possibly due to performance issue or insufficient disk space), vReplicator will fail. To fix this, make sure there's enough free space and then just remove this snapshot manually through Snapshot Manager. After it reaches 95%, be patient as it may take a very long time depending on the virtual disk size to commit the snapshot. If it still fails, try creating a new snapshot and then select "Delete All".

Refs:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1003302
http://communities.vmware.com/thread/274077
http://communities.vmware.com/thread/121642