Hi perem,
Based on my understanding, the issue is that you cannot open a solution by Visual Studio 2005 for it has been upgraded to VS.NET 2008 type. Since you want to generate the output by Web Development Project, you wonder if there is a command tool to do that. If I have misunderstood your concern, please let me know.
For the command tool of this issue, please refer to the following link for using ?aspnet_merge.exe?.
Managing ASP.NET Precompiled Output for Deployment Using the aspnet_merge.exe Command
http://msdn2.microsoft.com/en-us/library/aa479044.aspx
Alternatively, you can use WDP for Visual Studio 2008 which is available now.
Visual Studio? 2008 Web Deployment Projects - December 2007 CTP
http://www.microsoft.com/downloads/details.aspx?FamilyID=0FF6B63F-F79D-4590-B619-A2A4E06820F0&displaylang=en
However, if you still want to use Visual Studio 2005 as your development tool, you can create a new solution/project by Visual Studio 2005, and then add the source files back by ?Add Existing Item??. Build the website and fix all the errors (Visual Studio 2008 may add some namespace in souce file and configurations in web.config). At last, re-create a Web Deployment Project based on the recovered web project.
Sincerely,
Benson Yu
Microsoft Online Community Support
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