Can Sony Ericsson s500 set SMS and power-on password?

The setting method of the power-on password is: menu → mobile phone settings → general → security → security lock → mobile phone security function → modify password → "Return to superior" → security function → select "Open".

If you want to cancel, please go to "Security Features" and select "Close" as mentioned above.

If you want to set it again in the future, you don't need to set a password, just select "Open".