在安装 net core2.1 是 发生错误，一直提示找不到系统路径，一下是错误日志：
[4880:2C0C][2018-12-19T17:53:47]i001: Burn v3.10.4.4718, Windows v10.0 (Build 17134: Service Pack 0), path: C:\WINDOWS\Temp\{F1C720BB-AF42-4EF5-839B-76FD09FCF725}\.cr\dotnet-sdk-2.1.202-win-x64.exe
[4880:2C0C][2018-12-19T17:53:47]i000: Initializing string variable 'DOTNETHOME' to value '[ProgramFiles6432Folder]dotnet'
[4880:2C0C][2018-12-19T17:53:47]i000: Initializing string variable 'BUNDLEMONIKER' to value 'Microsoft .NET Core SDK - 2.1.202'
[4880:2C0C][2018-12-19T17:53:47]i009: Command Line: '-burn.clean.room=C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.Net.Core.SDK,version=15.8.27924.0,chip=x64\dotnet-sdk-2.1.202-win-x64.exe -burn.filehandle.attached=576 -burn.filehandle.self=596 "C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise" /log C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK.log /quiet /norestart'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleOriginalSource' to value 'C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.Net.Core.SDK,version=15.8.27924.0,chip=x64\dotnet-sdk-2.1.202-win-x64.exe'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleOriginalSourceFolder' to value 'C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.Net.Core.SDK,version=15.8.27924.0,chip=x64\'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleLog' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleName' to value 'Microsoft .NET Core SDK - 2.1.202 (x64)'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleManufacturer' to value 'Microsoft Corporation'
[4880:4BD4][2018-12-19T17:53:47]i000: Setting numeric variable 'WixStdBALanguageId' to value 1033
[4880:4BD4][2018-12-19T17:53:47]i000: Setting version variable 'WixBundleFileVersion' to value '2.1.202.0'
[4880:2C0C][2018-12-19T17:53:47]i100: Detect begin, 5 packages
[4880:2C0C][2018-12-19T17:53:47]i103: Detected related package: {0AB9299C-9543-32D0-AA75-63401E0F399C}, scope: PerMachine, version: 2.0.12421.0, language: 0 operation: MajorUpgrade
[4880:2C0C][2018-12-19T17:53:47]i101: Detected package: dotnet_runtime_2.0.9_win_x64.msi, state: Absent, cached: None
[4880:2C0C][2018-12-19T17:53:47]i101: Detected package: dotnet_hostfxr_2.0.9_win_x64.msi, state: Absent, cached: None
[4880:2C0C][2018-12-19T17:53:47]i101: Detected package: dotnet_host_2.0.9_win_x64.msi, state: Absent, cached: None
[4880:2C0C][2018-12-19T17:53:47]i101: Detected package: dotnet_sdk_internal_2.1.202_win_x64.msi, state: Absent, cached: None
[4880:2C0C][2018-12-19T17:53:47]i101: Detected package: AspNetCoreRuntimePackageStore_x64, state: Absent, cached: None
[4880:2C0C][2018-12-19T17:53:47]i199: Detect complete, result: 0x0
[4880:2C0C][2018-12-19T17:53:47]i200: Plan begin, 5 packages, action: Install
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleRollbackLog_dotnet_runtime_2.0.9_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_000_dotnet_runtime_2.0.9_win_x64.msi_rollback.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleLog_dotnet_runtime_2.0.9_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_000_dotnet_runtime_2.0.9_win_x64.msi.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleRollbackLog_dotnet_hostfxr_2.0.9_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_001_dotnet_hostfxr_2.0.9_win_x64.msi_rollback.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleLog_dotnet_hostfxr_2.0.9_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_001_dotnet_hostfxr_2.0.9_win_x64.msi.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleRollbackLog_dotnet_host_2.0.9_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_002_dotnet_host_2.0.9_win_x64.msi_rollback.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleLog_dotnet_host_2.0.9_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_002_dotnet_host_2.0.9_win_x64.msi.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleRollbackLog_dotnet_sdk_internal_2.1.202_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_003_dotnet_sdk_internal_2.1.202_win_x64.msi_rollback.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleLog_dotnet_sdk_internal_2.1.202_win_x64.msi' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_003_dotnet_sdk_internal_2.1.202_win_x64.msi.log'
[4880:2C0C][2018-12-19T17:53:47]i052: Condition 'VersionNT64' evaluates to true.
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleRollbackLog_AspNetCoreRuntimePackageStore_x64' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_004_AspNetCoreRuntimePackageStore_x64_rollback.log'
[4880:2C0C][2018-12-19T17:53:47]i000: Setting string variable 'WixBundleLog_AspNetCoreRuntimePackageStore_x64' to value 'C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_004_AspNetCoreRuntimePackageStore_x64.log'
[4880:2C0C][2018-12-19T17:53:47]i201: Planned package: dotnet_runtime_2.0.9_win_x64.msi, state: Absent, default requested: Present, ba requested: Present, execute: Install, rollback: Uninstall, cache: Yes, uncache: No, dependency: Register
[4880:2C0C][2018-12-19T17:53:47]i201: Planned package: dotnet_hostfxr_2.0.9_win_x64.msi, state: Absent, default requested: Present, ba requested: Present, execute: Install, rollback: Uninstall, cache: Yes, uncache: No, dependency: Register
[4880:2C0C][2018-12-19T17:53:47]i201: Planned package: dotnet_host_2.0.9_win_x64.msi, state: Absent, default requested: Present, ba requested: Present, execute: Install, rollback: Uninstall, cache: Yes, uncache: No, dependency: Register
[4880:2C0C][2018-12-19T17:53:47]i201: Planned package: dotnet_sdk_internal_2.1.202_win_x64.msi, state: Absent, default requested: Present, ba requested: Present, execute: Install, rollback: Uninstall, cache: Yes, uncache: No, dependency: Register
[4880:2C0C][2018-12-19T17:53:47]i201: Planned package: AspNetCoreRuntimePackageStore_x64, state: Absent, default requested: Present, ba requested: Present, execute: Install, rollback: Uninstall, cache: Yes, uncache: No, dependency: Register
[4880:2C0C][2018-12-19T17:53:47]i299: Plan complete, result: 0x0
[4880:2C0C][2018-12-19T17:53:47]i300: Apply begin
[4880:2C0C][2018-12-19T17:53:47]i010: Launching elevated engine process.
[4880:2C0C][2018-12-19T17:53:47]i011: Launched elevated engine process.
[4880:2C0C][2018-12-19T17:53:47]i012: Connected to elevated engine.
[1EDC:32A0][2018-12-19T17:53:48]i358: Pausing automatic updates.
[1EDC:32A0][2018-12-19T17:53:48]i359: Paused automatic updates.
[1EDC:32A0][2018-12-19T17:53:48]i370: Session begin, registration key: SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{06b884b0-4947-4439-859f-098e431012d6}, options: 0x7, disable resume: No
[1EDC:32A0][2018-12-19T17:53:48]e000: Error 0x80070003: Failed to create cache directory: C:\ProgramData\Package Cache\{06b884b0-4947-4439-859f-098e431012d6}\
[1EDC:32A0][2018-12-19T17:53:48]e000: Error 0x80070003: Failed to create completed cache path for bundle.
[1EDC:32A0][2018-12-19T17:53:48]e000: Error 0x80070003: Failed to cache bundle from path: C:\WINDOWS\Temp\{563CD0DD-3D1C-4C6E-BC7C-36B60D749270}\.be\dotnet-sdk-2.1.202-win-x64.exe
[1EDC:32A0][2018-12-19T17:53:48]e000: Error 0x80070003: Failed to begin registration session.
[4880:2C0C][2018-12-19T17:53:48]e000: Error 0x80070003: Failed to begin registration session in per-machine process.
[4880:2C0C][2018-12-19T17:53:48]e000: Error 0x80070003: Failed to register bundle.
[4880:2C0C][2018-12-19T17:53:48]i399: Apply complete, result: 0x80070003, restart: None, ba requested restart: No
[4880:2C0C][2018-12-19T17:53:48]i500: Shutting down, exit code: 0x3
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: BUNDLEMONIKER = Microsoft .NET Core SDK - 2.1.202
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: DOTNETHOME = C:\Program Files\dotnet
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: ProgramFiles6432Folder = C:\Program Files\
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: VersionNT64 = 10.0.0.0
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleAction = 5
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleElevated = 1
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleFileVersion = 2.1.202.0
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleInstalled = 0
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleLog = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleLog_AspNetCoreRuntimePackageStore_x64 = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_004_AspNetCoreRuntimePackageStore_x64.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleLog_dotnet_host_2.0.9_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_002_dotnet_host_2.0.9_win_x64.msi.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleLog_dotnet_hostfxr_2.0.9_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_001_dotnet_hostfxr_2.0.9_win_x64.msi.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleLog_dotnet_runtime_2.0.9_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_000_dotnet_runtime_2.0.9_win_x64.msi.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleLog_dotnet_sdk_internal_2.1.202_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_003_dotnet_sdk_internal_2.1.202_win_x64.msi.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleManufacturer = Microsoft Corporation
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleName = Microsoft .NET Core SDK - 2.1.202 (x64)
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleOriginalSource = C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.Net.Core.SDK,version=15.8.27924.0,chip=x64\dotnet-sdk-2.1.202-win-x64.exe
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleOriginalSourceFolder = C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.Net.Core.SDK,version=15.8.27924.0,chip=x64\
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleProviderKey = {06b884b0-4947-4439-859f-098e431012d6}
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleRollbackLog_AspNetCoreRuntimePackageStore_x64 = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_004_AspNetCoreRuntimePackageStore_x64_rollback.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleRollbackLog_dotnet_host_2.0.9_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_002_dotnet_host_2.0.9_win_x64.msi_rollback.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleRollbackLog_dotnet_hostfxr_2.0.9_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_001_dotnet_hostfxr_2.0.9_win_x64.msi_rollback.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleRollbackLog_dotnet_runtime_2.0.9_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_000_dotnet_runtime_2.0.9_win_x64.msi_rollback.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleRollbackLog_dotnet_sdk_internal_2.1.202_win_x64.msi = C:\Users\Administrator\AppData\Local\Temp\dd_setup_20181219174354_154_Microsoft.Net.Core.SDK_003_dotnet_sdk_internal_2.1.202_win_x64.msi_rollback.log
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleSourceProcessFolder = C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.Net.Core.SDK,version=15.8.27924.0,chip=x64\
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleSourceProcessPath = C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.Net.Core.SDK,version=15.8.27924.0,chip=x64\dotnet-sdk-2.1.202-win-x64.exe
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleTag =
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixBundleVersion = 2.1.202.0
[4880:2C0C][2018-12-19T17:53:48]i410: Variable: WixStdBALanguageId = 1033
[4880:2C0C][2018-12-19T17:53:48]i007: Exit code: 0x3, restarting: No
虽然是个小问题，但是这里还是写出来告知下：
问题在于C:\ProgramData下的Package Cache文件夹，1.需要添加完全控制权限，2.如果这个文件是快捷类型的文件夹，你需要双击看看是否能正常打开，不能打开或者报错，就压把它删除，重建Package Cache文件夹；就能解决问题