I presume you mean Business Contact Manager in Office 2003? If so, then ...

-- BCM will disable itself if the profile contains an Exchange account. This
behavior is by design, but can be circumvented (but not in a supported
fashion). See http://www.slipstick.com/bcm/bcmfaq_more.aspx?id=52

-- If you don't see the Business Tools menu, BCM probably failed to load
when Outlook started. Run Regedit and go to the
HKLM\Software\Microsoft\Office\Outlook\Addins\Microsoft.BusinessSolutions.eCRM.OutlookAddin.Connect.1
key. If the value for LoadBehavior is something other than 3, make a backup
of the registry, edit LoadBehavior to set it to 3, then restart Outlook.

-- If you get errors during setup, if BCM does not load even after you edit
the LoadBehavior registry value, or if the database does not load, you
should initiate a support incident with Microsoft at
http://support.microsoft.com/default.aspx?scid=fh;en-us;incidentsubmit. You
will need a .Net Passport, but there should be no charge for filing the
request for help if you have a retail copy of Office.

FYI, there is a separate newsgroup for BCM issues --  
microsoft.public.outlook.bcm