6230i security code needed please

hi can anybody help me with my 6230i it keeps coming up
security code needed which i did have written down but have lost it?.
the phone is on o2 and the imei number is :- 358827004562280.
thanks in advance :O)

 

Dedault security code: 12345
or
IMEI: 358827004562280
Security Mastercode: 0673667604

 

excellent thanks worked a treat :O)

 

Thanks for the response