hi,  my  k800i  stop working,  if you  go  to  site, www,sonyericsson.com/support you  can  down  load  the  information  that  will  put the  software  back  on  your  phone,  just  follow  the  instructions,  you  will  need  the cable  that  connects  your  phone  to  the  usb  port  on  a  computer,  the  only  problem  is  that  you  could  lose  your  information,  i  did  with  my  picture's,  but  it's  the only  way  of  getting  your  phone  to  work  again.  best  wishes for  the  new  year.
                 tony  parker.
                
 December 2008