Exchange Server setup error

[TSCustomer]

We bought your course about how configure and manage Exchange Server 2007 in order to install this server in our organization.
We have 4 servers:
1 server 2000
1 SBS 2003 (upgraded to standard edition)
2 server 2003 standard edition, x32 and x64 bit respectively.

We already installed .net framework x64, mw power shell x64 version and the IIS with its setup. When we tried to run PrepareAD through setup program (on our server x64) we received message below:

E:\ExchangeSvr 2007>setup /PrepareAD /ON:arrayconnector
Welcome to Microsoft Exchange Server 2007 Unattended Setup
Preparing Exchange Setup
No server roles will be installed
Exchange organization name cannot be specified. There already exists an Exchange
organization with name 'First Organization'.
Exchange Server setup encountered an error.


Have you seem this message before?

Could it be related to SBS 2003 we have installed in our domain?

Any help with this issue will be greatly appreciated.

[Gosia]

I haven’t seen that error in our environment but I was able to find few links that may give you a solution.

I would start with looking at the Even Viewer logs and Exchange logs for more information. See if maybe you get an error code or more detailed description of the problem. Here are the links that I found:

http://support.microsoft.com/ph/10926/en-us/?aid=3&GSA_AC_More3

http://www.msexchange.org/ (In order to view articles you will need to register with their site - It’s a free registration.)