- a Sandisk 4 GB microSDHC card works perfectly for me.
- When you try to insert the card into your phone, you need to pull the card holder towards the SIM slot to unlock it. Then you can pull it up, insert the card and close and lock it again.
- You find the manual here: http://mymobile.three.co.uk:8080/mymobile/3/SkypephoneS2/img/S2UserGuide_UK.pdf
If you like this post, consider ordering a SIM via my three agent link.