i had the same problem...trust me i tryed three little drivers including a 00 and non of them worked. Then i went to kmart and got a 2-in-1 (phillips and flat) eyeglass screwdriver keychain and it worked perfectly. It also was small enough to fit straight in. cost $1.99 (and came with a pouch). Found it in the check out isle...
I would not push harder if other driver isn't working...then you WILL strip and then you have a serious problem...