Hi,
I haven't run into that problem so I don't have a clear solution for you. Just wanted to give some input in case no one ever replies to you. It's usually not necessary to interact with Outlook, since MAPIEx, POP3/SMTP, or the new Outlook VBO can automate most mail retrieval/send requirements.
Just checking here, but are you sure you need to open Outlook for your automations?
If you absolutely must interact with it that way, I would try the multiple ways there are to open applications. There's obviously starting by the Launch action of a Navigate stage, but you can also use the Start Process action of the Environment VBO and there are a couple other actions to attempt as well depending on your needs. You can also use a batch file to run Outlook, so that you have more options in how the application is run.
If you've tried all that, I would contact your BP rep and set up a call where you can show them the issue. It may be a matter of some startup argument you can provide, as you were trying, but maybe BP can provide you with a direct solution.
Dave Morris, 3Ci at Southern Company