EXFO FTB-500 (Window XP) - Manual (Page 198)

Preparing for Automation
188 FTB-500
Configuring DCOM Access to Your Unit
7. In the Access Permission dialog box, ensure that the Distributed COM
Users group appears in the Group or user names list.
You can now allow users to access general DCOM services on your
FTB-500. You can either:

Add a user to the Distributed COM Users group (refer to Microsoft
help).
OR

Add a user explicitly under both, Access Permission and Launch
Permission tabs (see procedure below).
Note: If you add a user explicitly, ensure to give remote access rights to the new
user.