using proxy account in AX

Hello,

I am using proxy account for C# application that get some data from AX.

In C# I did:

using MIL = Microsoft.Dynamics.AX.ManagedInterop;

...

public static MIL.Session axSession = null;

...

MyAXClass s;

axSession = new MIL.Session();

axSession.logon(null, null, null, null);

...

s = new MyAXClass();

s.myAXFunction();

For some reason the class is execute on one environment, and isn't executed on other environment.

I see that there is no proxy account for the specific environment, I cannot execute the code.

I don't know whether that may be the reason.

What may be the reason for the class not to be executed on a specific environment, and shall I declare the proxy account in users?

How is ax session connected? What is the default 'company' that is connected (first parameter)?

I have tried to add proxy account to ax, but I got an exception:

Cannot insert multiple records in Security user role (SecurityUserRole).
The record already exists.

Thanks :)