win2003 安裝了 sql2008 出現問題，重新卸載再安裝.net，報錯
解決步驟：
1、添加註冊表
After 22 hours of troubleshooting, I finally got to the root of the problem in my case! This may not work for everyone though
In regedit, browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Security\
Check for the existence of a key named 'ServiceModel 3.0.0.0' (without the quotes)
If it doesn't exist, create it.
Add Administators and give them Full Control in permissions.
Also add Full Control permission for System
I also added Everyone and gave Full Control as well, but I don't think this is necessary.
If your own user account is showing there, delete it.
Problem solved on the next install - now I can get some sleep!!
2、使用 Microsoft .NET Framework Cleanup Tool v2018.05免費中文版.exe 卸載所有
3、C:\WINDOWS\assembly 重新命名
4、重啓
5、啓動之後，關閉SQL2005所有服務 360等軟件
6、直接安裝.net3.5sp1 dotnetfx35.exe
7、安裝完成之後 .net 2 net3.5 都自動安裝上