Error while trying to read HMI users and roles

[Zeev]

Hi,

I'm new to Sysmac studio and I'm building a project that requires an Admin screen for adding /deleting users and roles

I was following a couple of topics here and understood that you can get a list of users  or roles by folowing:

Dim array(100) As String

Sub GetAllRoles
    array= System.Linq.Enumerable.ToArray(_Hmi_s_Roles())
    RolesBox.SetItems(array)
End Sub

Sub GetAllNames
    array= System.Linq.Enumerable.ToArray(_HMI_s_Users())
    NamesBox.SetItems(array)
End Sub    

It was working fine in simulation mode, but when I  downloaded it to PLC I got the following error:

"SafeArrayTypeMismatchException is thrown at CallMethod"

E_SYS_999: 0x80131533

Did anyone encountered it? Any workaround?

Thank you!