Maybe the downloaded files are corrupt:
Clear your internet cache.
Maybe your computer goes into sleep or hybernate mode during the process:
Make sure that the computer don't go to sleep or hybernate state during the process.
Plug the power adaptor in.
Right click the desktop, sellect properties.
Sellect the Screen saver tab.
Click the power options button.
Set it to "Presentation" or "Always active".
In that mode, all power saving features are turned OFF.
Be sure to reset it to your usual settings after the updates are completed, or your battery autonomy will be horrible.
Electro, October 2011
