Extension commands need mscorwks.dll in order to have something to do.的一种情况

今天开发人员提交同一个程序的两个dump文件，运行环境Windows Server 2008 R2、.NET Framework 2.0。当使用WinDbg分析第二个文件时，加载sos执行命令提示如下：

0:000> .load C:\Windows\Microsoft.NET\Framework64\v2.0.50727\sos.dll
0:000> !clrstack
Failed to find runtime DLL (mscorwks.dll), 0x80004005
Extension commands need mscorwks.dll in order to have something to do.

执行lmvm clr发现CLR为4.0，重新加载4.0版本的sos.dll可以解决该问题。

0:000> lmvm clr
start             end                 module name
00000000`71450000 00000000`71abf000   clr        (deferred)             
    Image path: C:\Windows\Microsoft.NET\Framework\v4.0.30319\clr.dll
    Image name: clr.dll
    Timestamp:        Thu Mar 18 15:44:47 2010 (4BA1D9EF)
    CheckSum:         00671FC0
    ImageSize:        0066F000
    File version:     4.0.30319.1
    Product version:  4.0.30319.1
    File flags:       8 (Mask 3F) Private
    File OS:          4 Unknown Win32
    File type:        2.0 Dll
    File date:        00000000.00000000
    Translations:     0409.04b0
    CompanyName:      Microsoft Corporation
    ProductName:      Microsoft® .NET Framework
    InternalName:     clr.dll
    OriginalFilename: clr.dll
    ProductVersion:   4.0.30319.1
    FileVersion:      4.0.30319.1 (RTMRel.030319-0100)
    PrivateBuild:     DDBLD766
    FileDescription:  Microsoft .NET Runtime Common Language Runtime - WorkStation
    LegalCopyright:   © Microsoft Corporation.  All rights reserved.
    Comments:         Flavor=Retail

补充一下，由于.NET Framework 4.5的安装实际替换了4.0目录下对应的文件，所以4.0以上版本的更新调试存在3个版本，调试时分别需要相应版本的clr.dll、mscordacwks.dll、sos.dl（v4.0.30319.1、v4.0.30319.17929、v4.0.30319.18010）。