A common work around required to make Outlook 2010 work with CRM 4.0 is to add the following registry key:
HKEY Current User\SOFTWARE\Microsoft\MSCRMClient
Create DWord (32 bit) value
Title: IgnoreChecks
Value: 1
NOTE:
- The installer will show an error but you will be able to continue.
- Remember that Dynamics CRM only supports the 32-bit Outlook Client.
Jeff Loucks
Available Technology 