hello friends can somebody helps me as i am not able to update my nokia e63 firmware to the latest v50 currently i have v410.21.010 installed i tried to install the latest firmware through nokia software updater as well as ovi updater , after downloading it shows the error that NSU has lost the connection to nokis e63 please switch off and on the phone and reconnect the cable and press ok.

what will be the possible issues for that
pls help me.