Error in Installing reQall 1.2.0 for Outlook

Hi experts! I recently tried to install reQall 1.2.0 for Outlook, but I received an error message saying that there is no supported version of Outlook (Outlook 2010 beta 32/64 bit, Outlook 2007, etc.) installed in my computer.

reQall for Outlook 1.2.0 Setup
No supported Outlook is installed
[Outlook 2010 (32/64 bit), 2007, 2003, 2002 or 2000] !
However, I already have Microsoft Outlook 2010 Beta installed and running on my computer.
What could be the problem?
Please help me out.
Thanks a lot in advance.
