1. Pressing ctrl-alt-del on the pc select Task Manager.
2. In taskmanager terminate the process called wcescomm.exe
3. switch of the phone, then switch it on holding the power and record button, after about a minute or so you will see a 3 coloured screen.
4. Connect cradle to pc and insert phone into cradle.
5. Run the sinunlockv_2 app
6. write down the code obtained from the unlock program
7. restart phone with sim card from another network (IE not the network you normally use Orange etc)
8. Enter code when prompted.
9. restart pc
NOTE by awarner to unlock your SPV or E100 you MUST have bootloader V.98 or below and also your PC must be running Win XP or 2K
EDIT 2 For bootloader V1.10 you will need the SPV Unlock V2 information for this can be found here
FOR MPX200 and E200 users you can SIM unlock your phone here