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This article describes the following aspects of the Microsoft .NET Framework 3.5 Service Pack 1 (SP1):

  • Hotfixes that are included in this service pack

  • New features and functionalities

Note This update also includes cumulative servicing updates to the dependent .NET Framework 2.0 and .NET Framework 3.0 subcomponents. This article applies to the 32-bit versions of the .NET Framework and to the 64-bit versions of the .NET Framework.

More Information

The .NET Framework 3.5 SP1 is a full cumulative update that contains many new features. These new features build incrementally upon the .NET Framework 2.0, the .NET Framework 3.0, and the .NET Framework 3.5. It also includes cumulative servicing updates to the dependent .NET Framework 2.0 and .NET Framework 3.0 subcomponents. This update should be applied as an important update for the .NET Framework 2.0 and later versions, and it is recommended for all other supported operating systems.

Hotfixes that are included in this service pack

Microsoft Knowledge Base article



FIX: Error message when you add a Web reference to a project in Visual Studio 2005: "The custom tool 'MSDiscoCodeGenerator' failed"


FIX: The System.Net.HttpWebRequest class may not maintain a persistent connection to a proxy in the .NET Framework 2.0


FIX: The XmlSerializer class generates an unexpected result when you use the XmlSerializer class to serialize the numeration attribute in the .NET Framework 2.0


FIX: You may experience delays when an operating system shuts down if the computer is running a managed service together with the .NET Framework 2.0


FIX: Certain Unicode characters returned by the Application.ExecutablePath property in the .NET Framework 2.0 are displayed as "?"


FIX: Error message when you use the SQL Native Client data provider to connect to an instance of SQL Server 2005 that is configured to use database mirroring: "Internal .Net Framework Data Provider error 6"


FIX: You cannot access tables that are used in a SQL Server transaction if you end the thread that executes the transaction before the transaction is finished in the .NET Framework 2.0


FIX: You may experience a significant delay when you make the first request to an ASP.NET Web application that is running on Windows Server 2003


FIX: An ActiveX control will not receive keyboard navigation events when you use a System.Windows.Forms.WebBrowser control to host Web pages


FIX: The input language in a text box on the Microsoft Expression Design surface does not function correctly when you change the input language to an East Asian language


FIX: Error message when you use the installer tool to install an assembly that is located on a remote computer: "An exception occurred during the Install phase"


FIX: The headers attribute of a cell is rendered incorrectly when the cell is associated with multiple headers in an ASP.NET 2.0 Web application


FIX: An installation may fail with error 1935 when an .msi file tries to install many policy files on a computer that has the .NET Framework 2.0 installed


FIX: Incorrect methods are called when you call some COM APIs that are included in a .NET Framework 2.0-based 64-bit application


FIX: In a Windows Forms application that was built by using the .NET Framework 2.0, the CurrencyManager object triggers additional instances of some events when you delete the last row from a table


FIX: An update package is available for the .NET Framework 2.0 Service Pack 1


FIX: The value of the "WsdlContractConversionContext.WsdlPortType" property is null in the .NET Framework 3.0 Service Pack 1


You receive a System.InvalidOperationException exception error when you run a Microsoft .NET Framework 2.0-based application after you install security update MS 07-040 on a computer


FIX: Objects are not serialized correctly when you serialize and deserialize the DataSet objects by using the SerializationFormat.Binary format parameter in a .NET Framework 2.0-based application


Availability of the .NET Framework 2.0 post-Service Pack 1 hotfix rollup package for System.Data.dll and System.Data.OracleClient.dll


FIX: You may receive a System.Xml.XmlException exception when you use one-way Web methods to communicate with Web services in a .NET Framework 3.0-based application


FIX: An exception occurs when a Web application that is based on the .NET Framework 2.0 uses the HttpWebRequest class and receives an HTTP 1.0 response that contains the HTTP status code 401


FIX: A Windows Forms application that uses ActiveX controls may crash, and a null reference exception occurs after you install the .NET Framework 2.0 Service Pack 1


FIX: Error message if you deploy an executable application to a path that contains escape characters in the .NET Framework 2.0: "Absolute path information is required"


FIX: You receive a System.ArgumentException exception error message when you use the Sgen.exe tool and the XmlSerializer JIT compiler to generate an XmlSerializer assembly for a Web service proxy in the .NET Framework 2.0


FIX: In the .NET Framework 2.0 Service Pack 1, the ModuleBuilder.GetTypeToken method returns an incorrect token


FIX: Warning message when you use the SvcUtil.exe tool to import service metadata in the .NET Framework 3.5: "The policy expression was not fully imported because it exceeded the maximum allowable complexity"


FIX: The set of values returned from the row.GetColumnsInError method is empty when a client computer that has the .NET Framework 2.0 installed receives a DataSet object from a WCF service


FIX: You cannot download the .application file when you deploy an application by using ClickOnce deployment in a secure environment

Known issues

Issue 1

After you install the .NET Framework 3.5 SP1 in Windows XP or Windows Server 2003, there is an arbitrary folder that is generated in the root of drive C. This folder contains two subfolders that are named amd64 and i386. These two subfolders both include the following files:

  • Filterpipelineprintproc.dll


  • Msxpsdrv.inf

  • Msxpsinc.gpd

  • Msxpsinc.ppd

  • Mxdwdrv.dll

  • Xpssvcs.dll

These files were pending to be deleted from the XPSEPSC installation.


To resolve this issue, delete the folder manually.

Issue 2

.NET Framework assistant for Firefox has the Uninstall button disabled. In the .NET Framework 3.5 SP1, the .NET Framework Assistant enables Firefox to use the ClickOnce technology that is included in the .NET Framework. The .NET Framework Assistant is added at the computer level so that its functionality can be used by all users at the computer level instead of at the user level. Therefore, the Uninstall button is unavailable in the Firefox Add-ons menu because standard users are not permitted to uninstall computer level components.


An update has been produced to resolve this issue and make this version of the .NET Framework Assistant for Firefox compatible with the next version of the Firefox browser. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

How to remove the .NET Framework Assistant for Firefox

New features and functionalities

  • ASP.NET Dynamic Data

  • Core improvements to the common language runtime. The improvements include better layout of the .NET Framework native images.

  • Performance improvements to Windows Presentation Foundation

  • Ability of ClickOnce application publishers to opt out of signing and hashing as appropriate for their scenarios.

An update for the .NET Framework 3.5 Service Pack 1 is available. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

An update for the .NET Framework 3.5 Service Pack 1 is available


Visit the following websites for more information about installing issue of the .NET Framwork 3.5 Service Pack 1

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