If you have a SKY digibox and don't have a new SKY freeview card then you may have lost Channel 5, Five US and Fiver.  You may also have reverted back to ITV London and BBC London.

If so then you will find that the regional BBC channels can be found listed in the programming guide but NOT the ITV ones.

You CAN get the ITV channel you want and also Channel 5 but not Fiver or Five US.  Here is how;

On your SKY remote press the following;
Services
4 (System Setup)
4 (Add channels)
Enter
Frequency: 10773
Polarity: H (use arrow key)
Symbol Rate:22 (use arrow key)
FEC: 5/6 (use arrow key)
Find Channels

Some channels should now appear, among them 'Five'
Select 'Five' and press the yellow button
Press Select/Select/Backup/Backup

Five will NOT appear in the TV guide but you can access it by pressing Services/7 Other Channels

You can follow the same procedure to add in your local ITV region.  Frequencies etc. can be found here or ask!
http://www.lyngsat.com/28east.html

Nigel