1) Take out the battery and clean the contacts (battery & phone) with an earbud & WD40. If that doesn't work
2) Menu, Settings, General tab, Update service and search for an update on your phone
OR
3) Go to Sonyericsson.com, click on the support tab, click on the update service tab and press the download link. once thats done run the program, select your phone and follow the instructions to the letter. DO NOT REMOVE THE USB LEAD UNTIL YOUR PROMPTED cos this WILL result in your phone becoming an expensive paperweight!!!
Billy Wiz..., March 2008