Updates fail - help!

[trees-r-green]

Hi,

Every time I try to install updates they download and initially install fine, but when I reboot they won't configure properly and I get the message 'updates not configured, revert changes' or something similar.

I've tried disabling my anti-virus and cleared out some temp files in the software distribution folder (as advised online) but still no joy.

Any help would be so welcome!