you have to have all the phones near the main base. press and hold find on the base until a green light flashes. take your first phone then press menu then scroll till you find registration then select register handset then do the same for all other handsets. a full user manual is available http://www.shop.bt.com/content/uni2/documentation/5fjc/full_user_guide.pdf
hope this helps it took me ages to find the answer
julie, November 2009
