• Chart: Vista Compatibility for Visual Studio

Visual Studio (VS) 2005 SP1, which will consist solely of bug fixes, is due by the end of 2006 and will be followed by a patch that will let developers run VS 2005 on Windows Vista. Besides Visual Basic (VB) 6.0, which Microsoft made a special commitment to support on Windows Vista, the combination of VS 2005, SP1, and the expected patch will be the only supported version of VS on Vista. Developers using older versions of VS and considering upgrading to Vista must also upgrade to VS 2005 or use virtualization technology such as Virtual PC or VMware.

The support policy affects only the VS tools, not applications built with those tools—previous versions of the .NET Framework are supported on Windows Vista.

Vista Compatibility Coming

All versions of VS are affected by some architectural changes in Vista. These changes make the OS more resistant to attack by malicious software and reduce damage from poorly designed software, but they also interfere with developer tools.

The most important change is the introduction of User Account Control (UAC), a feature that allows users to run with less than full administrative privileges, but to temporarily elevate their privileges as needed. When a user attempts to perform an action that requires administrative privileges, such as changing network settings or installing an application, Vista presents a dialog box asking the user to authorize the task. Depending on the OS configuration, the user may be able to simply click OK or may have to enter a password.

UAC creates problems for developer tools, which require full administrative privileges. Debugging, for example, requires one application on the system (the developer tool) to be able to start, stop, modify, and access the memory of another application on the system (the program being debugged.) These are the same kinds of activities often performed by malware, which UAC is designed to thwart.

A patch (which Microsoft is calling a General Distribution Release, or GDR) that is due shortly after Windows Vista will fix problems with UAC, and other compatibility issues, to enable VS 2005 with SP1 to work properly on Windows Vista. The combination of VS 2005, SP1, and the patch will be the only version of VS fully supported on Vista, which means that some developers could choose to defer upgrading to Vista and stay on Windows XP. Other alternatives include using developer tools in a Windows XP guest OS running in a virtual machine hosted on Vista, or even turning UAC off, although turning off UAC makes a system more vulnerable to security threats, and Microsoft does not recommend it.

Microsoft is making an exception for VB 6 and will support it on Windows Vista. VB's internal architecture is quite different from VS's, and the product requires no technical changes to run on Vista, as long as the user has administrative privileges. VB 6 moved from Mainstream to Extended support on March 31, 2005, but many corporate developers continue to use the product to maintain important business applications, and Microsoft will provide these developers with the usual Extended support (which requires a fee-based contract in order to receive nonsecurity hotfixes).

(For a summary of how Vista supports various versions of Microsoft's developer tools, see the chart "Vista Compatibility for Visual Studio".)

User Account Control is explained in "User Account Control to Limit Vista Exploits" on page 3 of the Feb. 2006 Update.

The Visual Studio Product Feedback Center is at connect.microsoft.com/feedback/default.aspx?SiteID=210.