These documents provide important information you should know prior to deploying and using the Windows Server 2008 operating system, including known issues that you may need to avoid or work around.
The documents are continuously updated, so you should check this location for updated versions periodically.
You will find four documents for Windows Server 2008 R2:
Installing includes steps you should take prior to installing or upgrading to this release, supported upgrade paths, and any known issues that you may need to avoid or work around before starting the installation process. Release Notes focuses on the most critical issues, such as those that are likely to affect a majority of users and may cause data loss, installation failure, and security issues.
Things to Know is a collection of less-serious issues that are likely to affect a smaller number of users and have milder consequences if they are not avoided. Currently, all issues are reported in Release Notes; this document is essentially a placeholder at this time.
Copyright Attributions is a list of copyrights on images and technologies licensed for inclusion in Windows Server 2008 R2.
You should check all three documents for the most complete collection of issues known at this time.