Robot Ouputs not controlling my gripper solenoids

Hi

On my training course for the fanuc robots (2 wks ago)the grippers were all controlled via robot outputs.
I've tried the same thing with this 420-iF, using the RO[1] = on,RO[2]= off etc.. to get the solenoids to fire, but they wont.
There are 8 RO[n] defined on the TP the rest are not defined (of 24 i think).

Am i missing something here?
RI and RO are pre-assigned so why would they not work?
Would a gripper be wired into any other type of outputs?
I have just remastered this robot, it hadnt been turned on in a long time.
I dont know if there was software for this gripper on robot prior to remastering.
any ideas would be great
thanks

never used a i series- in the old Karels you have to set the user signal assignment table values for the I/O. I havent even setup a R-J in long enough that I dont recall if they needed them or not- anyway in the old Karels $USAT[87],[88]& [89] were the ones that configured hand#1...the first word says what slot the cards located in, the second the start address, and lastly the type of output- maintained/pulsed/etc...
imagine similar settings are required for the newer ones to tell the control what kind of hand you have mounted?