How do you reset-sim lock off samsung GT-C3303?

Resetting the simlock is not correct terminology, you turn the simlock off.

There are many reset codes that reset the whole phone but it is not smart to use these. They will reset the phone settings which sometimes includes calibration settings which will ruin your phone (sometimes 'phone freeze' message will appear making the phone useless until you repair it or your reception will be bad to non existent; not repairable).

To unlock a Samsung C3050 you have several options:

- unlock by IMEI (google for it many sites offering)

- unlock by cable remote (also just google unlock Samsung C3050) you will need original usb cable

- bring it to unlock shop

Always be very careful with choosing website or unlock shop. There are many amateurs and fake websites.

- google adds on site = fake

- In shop make sure they use solutions like: NSpro, UST, Easybox, SRS and couple others

- Check support options

- check feedback

- check blog (if they update the site regularly)

- check price - < 10 euros it will be FAKE