Get all instances of process

Hi,

I would like to get all instances of process in my process engine using :
pub.monitor.process.instance:getInstanceListCustomData
pub.monitor.process.instance:getInstanceListCustomDataSet

this two services return null in all cases (even if there are no criteria)

Can you help me to understand why this services not working

Thank you in advance.

Have you try with the Administrator user ? just for testing.

Thank you Arnaud, effectively the problem comes from my account
i have tested with Admininistrator user and the services working properly
I think that i should be configure my user profile to get some rights to execute this services

Thunk you one again