I uninstalled Client Access Role and now I'm reinstalling it but I get the error below. I have restarted the server many times but I still get this error.Summary: 1 item(s). 0 succeeded, 1 failed. Elapsed time: 00:01:09 Client Access Role PrerequisitesFailed Error:A reboot from a previous installation is pending. Please restart the system and rerun setup. Error:The 'IIS 7 Dynamic Content Compression' component is required. Install the component via Server Manager.Recommended Action: http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.3&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error:The 'IIS 7 Digest Authentication' component is required. Install the component via Server Manager.Recommended Action: http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.3&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Elapsed Time: 00:01:09

Hi,From the issue I note thatit ask usto install IIS Dynamic Content Compression component and IIS 7 Digest Authentication component first.So before we move on to install Client Access(CAS) Role, we need to install the component which are listing below (I assume that you are going to install CAS on Windows Server 2008.) ASP.NET ISAPI Extensions ISAPI Filters Server Side Includes .NET Extensibility Basic Authentication Windows Authentication Digest Authentication Dynamic Content Compression IIS 6 Management Compatibility So for this issue, I recommend you to check and install components that Exchange needs. Detail steps you can refer to the article below: How to Install Exchange 2007 SP1 Prerequisites on Windows Server 2008 or Windows Vista http://technet.microsoft.com/en-us/library/bb691354.aspx Regards, Xiu