Just something to add here. Make sure your using the best download server:
Go to 'Software & Updates'
Click 'Other' on 'Download from'
Click 'Select Best Server'
Let the test run.
Click 'Choose Server'
Go to 'Software & Updates'
Click 'Other' on 'Download from'
Click 'Select Best Server'
Let the test run.
Click 'Choose Server'