Stock recovery

[Seditec]

Can you flash a custom rom from our stock recovery

 

[blackops1125]

Can you flash a custom rom from our stock recovery

No you need a custom recovery

 

[hlxanthus]

Can you flash a custom rom from our stock recovery

Nope, you have to root, install a compatible custom recovery (xionia from this forum is the most widely used for the OptiS ) and then you can install a custom rom.

Edit: btw if you do decide to root, do NOT use Rom Manager, it will brick your phone