Before you begin installing Communicator Web Access (2007 R2 release), make sure that the computer does not have an underscore in its fully qualified domain name (FQDN) (for example, Internet Explorer does not support underscores in fully qualified domain names. If the Communicator Web Access server has an underscore in its name and if you are using integrated password authentication, no one using Internet Explorer will be able to log on to the Web site.

The recommended minimum hardware for a Communicator Web Access server is as follows:

As a general rule, increasing the speed of the processor, the hard disk, or the network card has a minimal effect on Communicator Web Access performance. If you wish to increase the performance (and the capacity) of your Communicator Web Access servers the best way to do this is to add additional memory.

Communicator Web Access (2007 R2 release) can only be installed on a computer running a 64-bit version of Microsoft Windows Server 2003 or Microsoft Windows Server 2008. This is an important change from the previous version of Communicator Web Access, which could run under either 32-bit or 64-bit versions of Windows. Communicator Web Access (2007 R2 release) must be installed on a computer running one of the following operating systems:

In addition, the following software must be running before Communicator Web Access can be installed:

If you install Communicator Web Access by using the Office Communications Server 2007 R2 Deployment Wizard, the Setup program will verify that each of these applications have been installed. If any of the applications are missing, the Deployment Wizard will notify you and offer to install the program for you. If you install Communicator Web Access from the command line, you will need to install each of these applications before you begin the setup.