FIX: Access violation may occur when you run a .NET Framework 2.0 SP2-based application that calls a mixed assembly that is domain-neutral

Applies to: .NET Framework 3.5 Service Pack 1


When you run a Microsoft .NET Framework 2.0-based application that calls a mixed assembly that is domain-neutral, an access violation error may occur. This error may cause some other issues. For example, this access violation error may cause the following issues:
  • If you have installed the Hub Transport Server Role or Edge Transport Server Role of Microsoft Exchange Server, the Exchange Transport service cannot start and you receive the following error message:
    Module load completed but symbols could not be loaded for
  • Some commands cannot be executed successfully in a client application that runs Exchange cmdlets in the Windows PowerShell prompt.


This issue is caused by a race condition that occurs when the assembly is loaded by multiple threads in multiple application domains. In this case, the common language runtime (CLR) only partially loads the assembly and does not fully initialize the types in the assembly. Therefore, when a process accesses the uninitialized part of the assembly, an access violation occurs.


Hotfix information

A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

To resolve this problem immediately, contact Microsoft Customer Support Services to obtain the hotfix. For a complete list of Microsoft Customer Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:
Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.


To apply this hotfix, you must have the .NET Framework 3.5 Service Pack 1 (SP1) installed on one of the following operating systems:
  • Windows Vista SP2
  • Windows Server 2008 SP2
Note The .NET Framework 2.0 SP2 is included in the .NET Framework 3.5 SP1.

Restart requirement

Before you apply this hotfix, we recommend that you exit all instances of Visual Studio and all .NET Framework-based applications. You do not have to restart the computer after you apply the hotfix if the affected files are not being used.

Hotfix replacement information

This hotfix does not replace any other hotfix.

File Information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

File information for all supported x86-based versions of Windows Vista SP2 and of Windows Server 2008 SP2
File nameFile versionFile sizeDateTimePlatform
Mscorlib.dll2.0.50727.56514,550,65603-Feb- 201110:55x86
Mscordacwks.dll2.0.50727.5651989,52803-Feb- 201110:54x86
Mscorwks.dll2.0.50727.56515,924,17603-Feb- 201110:55x86
Sos.dll2.0.50727.5651388,93603-Feb- 201110:55x86
File information for all supported x64-based versions of Windows Vista SP2 and of Windows Server 2008 SP2
File nameFile versionFile sizeDateTimePlatform
Mscorlib.dll2.0.50727.56514,567,04003-Feb- 201110:53x64
Mscordacwks.dll2.0.50727.56511,755,48003-Feb- 201110:52x64
Mscorwks.dll2.0.50727.56519,992,52803-Feb- 201110:53x64
Sos.dll2.0.50727.5651485,19203-Feb- 201110:54x64
File information for all supported IA-64-based versions of Windows Server 2008 SP2
File nameFile versionFile sizeDateTimePlatform


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

More Information

For more information about mixed (native and managed) assemblies, visit the following Microsoft Developer Network (MSDN) website:
For more information about application domains and assemblies, visit the following MSDN website:
For more information about Exchange Server Roles in Exchange Server 2010, visit the following Microsoft website:

Additional file information

Additional file information for all x86-based versions of Windows Vista Service Pack 2 (SP2) and of Windows Server 2008 SP2
File nameX86_mscorlib_b77a5c561934e089_6.0.6002.22582_none_b0cca9fadb4ceb9e.manifest
File versionNot Applicable
File size544,632
Date (UTC)03-Feb-2011
Time (UTC) 19:06
File nameX86_netfx- mscordacwks_b03f5f7f11d50a3a_6.0.6002.22582_none_14379bcf20d55bf6.manifest
File versionNot Applicable
File size6,241
Date (UTC) 03-Feb-2011
Time (UTC)19:03
File nameX86_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.0.6002.22582_none_1b7378e848d45023.manifest
File versionNot Applicable
File size25,247
Date (UTC)03-Feb-2011
Time (UTC)19:06
File nameX86_netfx- sos_dll_b03f5f7f11d50a3a_6.0.6002.22582_none_fd05e39014ca380b.manifest
File versionNot Applicable
File size4,115
Date (UTC) 03-Feb-2011
Time (UTC)19:02
Additional file information for all x64-based versions of Windows Vista SP2 and Windows Server 2008 SP2
File nameAmd64_mscorlib_b77a5c561934e089_6.0.6002.22582_none_691f7323c6d0c298.manifest
File versionNot Applicable
File size607,386
Date (UTC)03-Feb-2011
Time (UTC) 17:04
File nameAmd64_netfx- mscordacwks_b03f5f7f11d50a3a_6.0.6002.22582_none_cc8a64f80c5932f0.manifest
File versionNot Applicable
File size6,267
Date (UTC) 03-Feb-2011
Time (UTC)17:02
File nameAmd64_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.0.6002.22582_none_d3c642113458271d.manifest
File versionNot Applicable
File size24,663
Date (UTC)03-Feb-2011
Time (UTC)17:04
File nameAmd64_netfx- sos_dll_b03f5f7f11d50a3a_6.0.6002.22582_none_b558acb9004e0f05.manifest
File versionNot Applicable
File size4,131
Date (UTC) 03-Feb-2011
Additional file information for all IA-64-based versions of Windows Server 2008 SP2
File nameIa64_mscorlib_b77a5c561934e089_6.0.6002.22582_none_b0cc87bcdb4d2382.manifest
File versionNot Applicable
File size607,375
Date (UTC)03-Feb-2011
Time (UTC) 16:11
File nameIa64_netfx- mscordacwks_b03f5f7f11d50a3a_6.0.6002.22582_none_1437799120d593da.manifest
File versionNot Applicable
File size6,257
Date (UTC) 03-Feb-2011
Time (UTC)16:09
File nameIa64_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.0.6002.22582_none_1b7356aa48d48807.manifest
File versionNot Applicable
File size24,611
Date (UTC)03-Feb-2011
Time (UTC)16:11
File nameIa64_netfx- sos_dll_b03f5f7f11d50a3a_6.0.6002.22582_none_fd05c15214ca6fef.manifest
File versionNot Applicable
File size4,124
Date (UTC) 03-Feb-2011