sqlserver2008r2实例安装失败，卸载好几次了，别的功能能安装成功，就是实例失败，Summary.txt如下:

Overall summary:
  Final result:                  SQL Server 安装失败。若要继续操作，请调查失败原因，更正问题，卸载 SQL Server，然后重新运行 SQL Server 安装程序。
  Exit code (Decimal):           -2068052377
  Exit facility code:            1212
  Exit error code:               1639
  Exit message:                  SQL Server 安装失败。若要继续操作，请调查失败原因，更正问题，卸载 SQL Server，然后重新运行 SQL Server 安装程序。
  Start time:                    2014-06-30 09:10:12
  End time:                      2014-06-30 09:12:25
  Requested action:              Install
  Log with failure:              C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\sql_engine_core_inst_Cpu32_1.log
  Exception help link:           http://go.microsoft.com/fwlink?LinkId=20476&ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=10.50.1600.1

Machine Properties:
  Machine name:                  LENOVO-PC
  Machine processor count:       4
  OS version:                    Windows 7
  OS service pack:               Service Pack 1
  OS region:                     中华人民共和国
  OS language:                   中文(中华人民共和国)
  OS architecture:               x86
  Process architecture:          32 位
  OS clustered:                  否

Product features discovered:
  Product              Instance             Instance ID                    Feature                                  Language             Edition              Version         Clustered
  Sql Server 2008 R2                                                       管理工具 - 基本                                2052                 Enterprise Edition   10.50.1600.1    否        
  Sql Server 2008 R2                                                       管理工具 - 完整                                2052                 Enterprise Edition   10.50.1600.1    否        
  Sql Server 2008 R2                                                       客户端工具连接                                  2052                 Enterprise Edition   10.50.1600.1    否        
  Sql Server 2008 R2                                                       客户端工具向后兼容性                               2052                 Enterprise Edition   10.50.1600.1    否        
  Sql Server 2008 R2                                                       客户端工具 SDK                                2052                 Enterprise Edition   10.50.1600.1    否        
  Sql Server 2008 R2                                                       Integration Services                     2052                 Enterprise Edition   10.50.1600.1    否        

Package properties:
  Description:                   SQL Server Database Services 2008 R2
  ProductName:                   SQL Server 2008 R2
  Type:                          RTM
  Version:                       10
  SPLevel:                       0
  Installation location:         E:\aaaaaaaa\x86\setup\
  Installation edition:          ENTERPRISE

用户输入设置:
  ACTION:                        Install
  ADDCURRENTUSERASSQLADMIN:      False
  AGTSVCACCOUNT:                 NT AUTHORITY\NETWORK SERVICE
  AGTSVCPASSWORD:                *****
  AGTSVCSTARTUPTYPE:             Manual
  ASBACKUPDIR:                   C:\Program Files\Microsoft SQL Server\MSAS10_50.MSSQLSERVER\OLAP\Backup
  ASCOLLATION:                   Chinese_PRC_CI_AS
  ASCONFIGDIR:                   C:\Program Files\Microsoft SQL Server\MSAS10_50.MSSQLSERVER\OLAP\Config
  ASDATADIR:                     C:\Program Files\Microsoft SQL Server\MSAS10_50.MSSQLSERVER\OLAP\Data
  ASDOMAINGROUP:                 <空>
  ASLOGDIR:                      C:\Program Files\Microsoft SQL Server\MSAS10_50.MSSQLSERVER\OLAP\Log
  ASPROVIDERMSOLAP:              1
  ASSVCACCOUNT:                  NT AUTHORITY\NETWORK SERVICE
  ASSVCPASSWORD:                 *****
  ASSVCSTARTUPTYPE:              Automatic
  ASSYSADMINACCOUNTS:            lenovo-PC\lenovo
  ASTEMPDIR:                     C:\Program Files\Microsoft SQL Server\MSAS10_50.MSSQLSERVER\OLAP\Temp
  BROWSERSVCSTARTUPTYPE:         Disabled
  CONFIGURATIONFILE:             C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\ConfigurationFile.ini
  CUSOURCE:                     
  ENABLERANU:                    False
  ENU:                           False
  ERRORREPORTING:                False
  FARMACCOUNT:                   <空>
  FARMADMINPORT:                 0
  FARMPASSWORD:                  *****
  FEATURES:                      SQLENGINE,REPLICATION,FULLTEXT,AS,RS
  FILESTREAMLEVEL:               0
  FILESTREAMSHARENAME:           <空>
  FTSVCACCOUNT:                  NT AUTHORITY\LOCAL SERVICE
  FTSVCPASSWORD:                 *****
  HELP:                          False
  IACCEPTSQLSERVERLICENSETERMS:  False
  INDICATEPROGRESS:              False
  INSTALLSHAREDDIR:              C:\Program Files\Microsoft SQL Server\
  INSTALLSHAREDWOWDIR:           C:\Program Files\Microsoft SQL Server\
  INSTALLSQLDATADIR:             <空>
  INSTANCEDIR:                   C:\Program Files\Microsoft SQL Server\
  INSTANCEID:                    MSSQLSERVER
  INSTANCENAME:                  MSSQLSERVER
  ISSVCACCOUNT:                  NT AUTHORITY\NetworkService
  ISSVCPASSWORD:                 *****
  ISSVCSTARTUPTYPE:              Automatic
  NPENABLED:                     0
  PASSPHRASE:                    *****
  PCUSOURCE:                    
  PID:                           *****
  QUIET:                         False
  QUIETSIMPLE:                   False
  ROLE:                          <空>
  RSINSTALLMODE:                 DefaultNativeMode
  RSSVCACCOUNT:                  NT AUTHORITY\NETWORK SERVICE
  RSSVCPASSWORD:                 *****
  RSSVCSTARTUPTYPE:              Automatic
  SAPWD:                         *****
  SECURITYMODE:                  <空>
  SQLBACKUPDIR:                  <空>
  SQLCOLLATION:                  Chinese_PRC_CI_AS
  SQLSVCACCOUNT:                 NT AUTHORITY\NETWORK SERVICE
  SQLSVCPASSWORD:                *****
  SQLSVCSTARTUPTYPE:             Automatic
  SQLSYSADMINACCOUNTS:           lenovo-PC\lenovo
  SQLTEMPDBDIR:                  <空>
  SQLTEMPDBLOGDIR:               <空>
  SQLUSERDBDIR:                  <空>
  SQLUSERDBLOGDIR:               <空>
  SQMREPORTING:                  False
  TCPENABLED:                    1
  UIMODE:                        Normal
  X86:                           False

  Configuration file:            C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\ConfigurationFile.ini

Detailed results:
  Feature:                       数据库引擎服务
  Status:                        失败: 请查看日志了解详细信息
  MSI status:                    失败: 请查看下面的详细信息
  MSI error code:                0x1639
  MSI log file location:         C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\sql_engine_core_inst_Cpu32_1.log
  MSI error description:        
  Configuration status:          已通过

  Feature:                       SQL Server 复制
  Status:                        失败: 请查看日志了解详细信息
  MSI status:                    失败: 请查看下面的详细信息
  MSI error code:                0x1639
  MSI log file location:         C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\sql_engine_core_inst_Cpu32_1.log
  MSI error description:        
  Configuration status:          已通过

  Feature:                       全文搜索
  Status:                        失败: 请查看日志了解详细信息
  MSI status:                    失败: 请查看下面的详细信息
  MSI error code:                0x1639
  MSI log file location:         C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\sql_engine_core_inst_Cpu32_1.log
  MSI error description:        
  Configuration status:          已通过

  Feature:                       Analysis Services
  Status:                        失败: 请查看日志了解详细信息
  MSI status:                    失败: 请查看下面的详细信息
  MSI error code:                0x1639
  MSI log file location:         C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\sql_as_Cpu32_1.log
  MSI error description:        
  MSI status:                    失败: 请查看下面的详细信息
  MSI error code:                0x1639
  MSI log file location:         C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\sql_engine_core_inst_Cpu32_1.log
  MSI error description:        
  Configuration status:          已通过

  Feature:                       Reporting Services
  Status:                        失败: 请查看日志了解详细信息
  MSI status:                    失败: 请查看下面的详细信息
  MSI error code:                0x1639
  MSI log file location:         C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\sql_engine_core_inst_Cpu32_1.log
  MSI error description:        
  Configuration status:          已通过

Rules with failures:

Global rules:

Scenario specific rules:

Rules report file:               C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20140630_090925\SystemConfigurationCheck_Report.htm

sql_engine_core_inst_Cpu32_1.log如下:

=== Verbose logging started: 2014/6/30  9:12:19  Build type: SHIP UNICODE 5.00.7601.00  Calling process: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\SQLServer2008R2\x86\setup100.exe ===
MSI (c) (54:84) [09:12:19:033]: Resetting cached policy values
MSI (c) (54:84) [09:12:19:033]: Machine policy value 'Debug' is 0
MSI (c) (54:84) [09:12:19:033]: ******* RunEngine:
           ******* Product: E:\aaaaaaaa\x86\setup\sql_engine_core_inst_msi\sql_engine_core_inst.msi
           ******* Action:
           ******* CommandLine: **********
MSI (c) (54:84) [09:12:19:034]: Client-side and UI is none or basic: Running entire install on the server.
MSI (c) (54:84) [09:12:19:034]: Grabbed execution mutex.
MSI (c) (54:84) [09:12:19:036]: Cloaking enabled.
MSI (c) (54:84) [09:12:19:036]: Attempting to enable all disabled privileges before calling Install on Server
MSI (c) (54:84) [09:12:19:036]: Incrementing counter to disable shutdown. Counter after increment: 0
MSI (s) (C0:A8) [09:12:19:041]: Running installation inside multi-package transaction E:\aaaaaaaa\x86\setup\sql_engine_core_inst_msi\sql_engine_core_inst.msi
MSI (s) (C0:A8) [09:12:19:041]: Grabbed execution mutex.
MSI (s) (C0:70) [09:12:19:042]: Resetting cached policy values
MSI (s) (C0:70) [09:12:19:042]: Machine policy value 'Debug' is 0
MSI (s) (C0:70) [09:12:19:042]: ******* RunEngine:
           ******* Product: E:\aaaaaaaa\x86\setup\sql_engine_core_inst_msi\sql_engine_core_inst.msi
           ******* Action:
           ******* CommandLine: **********
MSI (s) (C0:70) [09:12:19:043]: Machine policy value 'TransformsSecure' is 0
MSI (s) (C0:70) [09:12:19:043]: User policy value 'TransformsAtSource' is 0
MSI (s) (C0:70) [09:12:19:043]: Machine policy value 'DisableUserInstalls' is 0
MSI (s) (C0:70) [09:12:19:043]: Specified instance {B5153233-9AEE-4CD4-9D2C-4FAAC870DBE2} via transform :InstID01.mst;:InstName01.mst is already installed. MSINEWINSTANCE requires a new instance that is not installed.
MSI (s) (C0:70) [09:12:19:044]: MainEngineThread is returning 1639
MSI (s) (C0:A8) [09:12:19:045]: User policy value 'DisableRollback' is 0
MSI (s) (C0:A8) [09:12:19:046]: Machine policy value 'DisableRollback' is 0
MSI (s) (C0:A8) [09:12:19:046]: Incrementing counter to disable shutdown. Counter after increment: 0
MSI (s) (C0:A8) [09:12:19:046]: Note: 1: 1402 2: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Installer\Rollback\Scripts 3: 2
MSI (s) (C0:A8) [09:12:19:046]: Note: 1: 1402 2: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Installer\Rollback\Scripts 3: 2
MSI (s) (C0:A8) [09:12:19:046]: Note: 1: 1402 2: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Installer\InProgress 3: 2
MSI (s) (C0:A8) [09:12:19:046]: Note: 1: 1402 2: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Installer\InProgress 3: 2
MSI (s) (C0:A8) [09:12:19:046]: Decrementing counter to disable shutdown. If counter >= 0, shutdown will be denied.  Counter after decrement: -1
MSI (s) (C0:A8) [09:12:19:047]: Restoring environment variables
MSI (c) (54:84) [09:12:19:049]: Decrementing counter to disable shutdown. If counter >= 0, shutdown will be denied.  Counter after decrement: -1
MSI (c) (54:84) [09:12:19:049]: MainEngineThread is returning 1639
=== Verbose logging stopped: 2014/6/30  9:12:19 ===

 怎么办？？