Sum of inputs using grpsum

[ctyler2621]

This is what I have in the item:
grpsum("Canopy_Network","Reg_count","last","0")

Canopy_Network is the group, Reg_count is the key name on the access points that returns a 64bit integer of registered users on each radio using SNMPv2 and I want the last value for each access point in the Canopy_Network added together to get a total user count.

But when I try to add this to the 'Items' list, I get the following error:
Incorrect key format 'key_name[param1,param2,...]'

Could someone shed some light on this and tell me where the heck I've messed up.
:confused:

[ctyler2621]

I changed the ( ) to [ ]:
grpsum["Access_Points","Reg_count","last","0"]


Now it throws this error:
Key does not match grpfunc('group','key','itemfunc','numeric param')

So what the heck have I done wrong now?


Here is the original item from the items table in the template that I created and as you can plainly see, the key does in fact match:
Reg Count Reg_count 30 90 365 SNMPv2 agent Active

If there is anything else that I can provide, PLEASE, let me know and I'll post it asap.