Yes You can get the Code to unlock the Mobile Phone,you need Network Unlock code means Get from here Theunlockspot
and You need Security or password Unlock code means get from Service provider,Following the Instructions below and Unlock Sony Ericsson C905 from Network Lock.
Sony Ericsson C905 Unlocking Instructions
Do not enter any wrong unlock
codes on your Sony Ericsson C905 mobile phones. If you enter over a
certain amount of wrong unlock codes on your Sony Ericsson C905 mobile
phone, your phone may get hard locked and sometimes become unusable.
1 - Switch ON your Sony Ericsson C905 without
any SIM Card,
2 - Press the left arrow
3 - Press the button * twice
4 - Press the left arrow
5 - The message "Personalize with MNC2" will appear, (or you will have
displayed an unlock menu, select the lock you want to unlock)
6 - Enter the Unlock Code.
If your Sony Ericsson C905 does not have a left arrow button/key(e.g.
Sony Ericsson W950i) and on a few phones(not all) that have a "JOGDIAL"
you must press the "down arrow" key/button instead of the "left arrow"
key/button for step 2 & 4. We mean by "Down Arrow" to direct the
Jogdial down! In the Sony Ericsson W950i and some other models, the down
arrow button/key would be located on the side of the phone.