最近在学习一个产品Guidewire，配置这个ClaimCenter6.0产品的数据库使用的是SqlServer2008版本的,这个安装配置倒是没有什么问题的； 但是配置ClaimCenter7.0产品的数据库时，问题就来了，之前安装的SqlServer2008的版本太低了，不支持，由于SqlServer2008 R2
最近在学习一个产品Guidewire，配置这个ClaimCenter6.0产品的数据库使用的是SqlServer2008版本的,这个安装配置倒是没有什么问题的；
但是配置ClaimCenter7.0产品的数据库时，问题就来了，之前安装的SqlServer2008的版本太低了，不支持，由于SqlServer2008 R2版本跟SqlServer2008版本实例不同，
所以先要把SqlServer2008卸载掉，再重新安装SqlServer2008R2版本的；在卸载SqlServer2008的时候可是费了我不少时间啊，当时就是一直不能够完全的卸载，使用Windows自带的“添加/删除”工具，有些就是无法删掉，
查了很多的资料，最终找到了解决方案：
1）使用工具软件“Windows Install Clean Up” 来完成SqlServer2008的完全卸载工作，这个工具确实很方便，能够卸载掉“添加/删除”工具中无法卸载的软件；
2）卸载完SqlServer2008的组件之后，要将安装目录下的SqlServer的目录结构删掉；
3）最后腰删除注册表中的信息；
A：删除HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server
B：删除HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer
C：进入HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall and delete all the sub-keys referencing SQL Server.
D：Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services and delete all the keys referencing SQL Server.
这样SqlServer2008可以算是完全的卸载成功了，接下来可以放心的安装SqlServer2008R2的实例了。
资料参考：http://blogs.msdn.com/b/sreekarm/archive/2010/03/15/sql-express-is-not-installed-properly-steps-to-be-taken-before-reinstall-again.aspx
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