Microsoft started sending out invites to early adopters to download and test drive Windows 7 and Windows Server 2008 SP1 Beta, which're scheduled to release by the end of July 2010. Microsoft in this reagrd, published content designed to help testers take SP1 Beta out for a spin. The "Troubleshoot problems installing a service pack for Windows 7 or Windows Server 2008 R2" from Windows Help is an illustrative example.
Microsoft informing customer, that "you might get an "Installation wasn't successful" error message. The most common causes of this problem are: An inconsistency in Windows Servicing Store – a feature required to successfully install the service packs; A program on your computer, such as antivirus or antispyware programs, interfering with installation of service pack." To solve this problem, first download and run System Update Readiness Tool, try to install service pack again. If you still can't install the service pack, follow these steps: