Error 0x800705AD insufficient quota to complete reqd service

Error 0x800705AD insufficient quota to complete reqd service

What does this mean and how do I fix it?

I have had this message frequently when transferring files to/from a
networked USB
device (camera, external HDD), and think it has something to do with Vista's
stupid paranoid
permissions. Now

When copying from a camera connected to the Vista laptop via the network to
a USB external HDD connected to the XP machine and this happens it actually
corrupts the data. That didn't happen this time, copying from an interal DVD
drive on the laptop to the external HDD on the network, but it did refuse to
copy the last few files and any subsequent files from anywhere to anywhere
until you reboot.

What causes this and how is it fixed? It is not a matter of disabling quotas
on the XP machine - I have already done that.