One thing you can try is to reset the phone using the *#7370# code (do it as the first thing after switching the phone on) and press OK which I think is either the left or right soft key.
However please be aware that doing so will wipe ALL the data from your phone such as information in your calendar, contacts and so on.
In order to save your data you can use the PC Suite application to save and restore the data from your phone - this software can be found here :
g mail box i can set in my nokia n 70 but i can not set yahoo mail box.can you tell me incoming and...
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G MAIL BOX I CAN SET IN MY NOKIA N 70 BUT I CAN NOT SET YAHOO MAIL BOX.CAN YOU TELL ME INCOMING AND OUTGOING MAIL SERVER TO SET YAHOO MAIL BOX.