过去两天我一直在尝试安装 SQL Server Express 2017，但安装完成时出现错误，即数据库引擎服务和 SQL Server 复制无法安装。我也收到此错误弹出消息：
发生以下错误：对象引用未设置为对象的实例。
我还尝试了以下步骤，希望能解决这个问题： i) 使用 .NET 修复工具包检查和修复我的 PC 的 .NET v4.6。ii) 将 SQL Server 数据库引擎配置更改为NT AUTHORITY\NETWORK SERVICE和NT AUTHORITY\SYSTEM。iii) 尝试在安装后使用修复工具修复系统。
安装的错误日志：
Feature: Database Engine Services
Status: Failed
Reason for failure: An error occurred during the setup process of the feature.
Next Step: Use the following information to resolve the error, uninstall this feature, and then run the setup process again.
Component name: SQL Server Database Engine Services Instance Features
Component error code: -2147467261
Error description: Object reference not set to an instance of an object.
Error help link: https://go.microsoft.com/fwlink?LinkId=20476&ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=14.0.1000.169&EvtType=0x9C8C9C81%400x44A889F9&EvtType=0x9C8C9C81%400x44A889F9
Feature: SQL Server Replication
Status: Failed
Reason for failure: An error occurred for a dependency of the feature causing the setup process for the feature to fail.
Next Step: Use the following information to resolve the error, uninstall this feature, and then run the setup process again.
Component name: SQL Server Database Engine Services Instance Features
Component error code: -2147467261
Error description: Object reference not set to an instance of an object.
Error help link: https://go.microsoft.com/fwlink?LinkId=20476&ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=14.0.1000.169&EvtType=0x9C8C9C81%400x44A889F9&EvtType=0x9C8C9C81%400x44A889F9
and the error log after repairing the instance:
Feature: Database Engine Services
Status: Failed
Reason for failure: An error occurred during the setup process of the feature.
Next Step: Use the following information to resolve the error, and then try the setup process again.
Component name: SQL Server Database Engine Services Instance Features
Component error code: 0x84B40002
Error description: The SQL Server feature 'SQL_Engine_Core_Inst' is not in a supported state for repair, as it was never successfully configured. Only features from successful installations can be repaired. To continue, remove the specified SQL Server feature.
Error help link: https://go.microsoft.com/fwlink?LinkId=20476&ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=14.0.1000.169&EvtType=0x2841E06E%401204%402&EvtType=0x2841E06E%401204%402
Feature: SQL Server Replication
Status: Failed
Reason for failure: An error occurred for a dependency of the feature causing the setup process for the feature to fail.
Next Step: Use the following information to resolve the error, and then try the setup process again.
Component name: SQL Server Database Engine Services Instance Features
Component error code: 0x84B40002
Error description: The SQL Server feature 'SQL_Engine_Core_Inst' is not in a supported state for repair, as it was never successfully configured. Only features from successful installations can be repaired. To continue, remove the specified SQL Server feature.
Error help link: https://go.microsoft.com/fwlink?LinkId=20476&ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=14.0.1000.169&EvtType=0x2841E06E%401204%402&EvtType=0x2841E06E%401204%402
如果有人能在出现问题时向我建议新的解决方案来解决这个问题，那就太好了。（不过对 MS SQL Server 来说是全新的）