I had the opportunity to go to Berlin for TechEd Europe 2009.  I delivered a presentation on Application Compatibility and the rest of the time I hung out in the “Test your app on Win 7” and “Win 7 Developer drop in center”. I got some great questions from attendees.  I thought I’d blog some of the general Q&A. Thank you to all that stopped by the booth. I loved Berlin.  I hope I get to go back soon.

 

Q: Do I need to worry about anything in Windows 7 for web apps?

A: There are some IE8 changes that may affect web applications. The Internet Explorer 8 Readiness Toolkit is a very good reference.  The developer checklist is a good place to start.

 

Q: What do I need to worry about for existing installers on Windows 7?

A: The common problems that are encountered with existing installers are the same issues encountered in Vista:

  • Version check criteria
  • MSI custom actions

Ideally, you should not check for version if possible. Version checking tends to block applications that may install and run just fine on a newer OS.  If you need to check version, you should display a warning rather than exiting the installation. Version checking can also cause issues after an upgrade with uninstall. If you check version, the user may not be able to uninstall your application after an upgrade to the new OS.

MSI custom actions can run in a standard user context or the administrator. Sometimes the custom action is running in the wrong context.  Chris Jackson has a great post on the common issue with deferred custom actions.

Q: Where can I find info on developing on Windows 7?

A: The Windows 7 Developer Guide gives a good overview of new developer functionality.  If you are looking for presentations and code samples to get you started, check out the Windows 7 Developer Jumpstart Kit.

 

Q: I’m a .NET Developer. What’s the guidance for developing on Windows 7? Should I use the Code Pack or wait for .NET 4.0?

A: The short answer is: Use the Code Pack today but think of it as free code to include in your application that wraps the native Windows 7 API’s. In .NET 4.0, you will see some of the new Windows developer features available in WPF.  Yochay Kiriaty has recently outlined guidance on this topic.

 

Q: .NET 1.1 SP1 support for Windows 7?

A: As with all older products, be sure to check the support lifecycle for the product first. There isn’t an official statement of .NET 1.1 SP1 compatibility for Windows 7. However, because compatibility was a key goal between Vista and Windows 7, efforts were made to ensure .NET 1.1 SP1 works on Windows 7.

 

Q: Does <insert app name here> work on Windows 7?

A: The Compatibility Center is the best reference to get information on what applications have been reported to be compatible with Windows 7.