Hi,
Based on my understanding, when you use VWD Express Edition open or create website on vista machine, VWD crashes.
Please install the Visual Web Developer 2005 Express SP1 and SP1 Update for Windows Vista. You can download them from http://www.microsoft.com/express/2005/download/default.aspx.
Since it worked before, did you install Add-In for it? If so, you can disable it and then run it. This can eliminate the possibility that third party Add-ins are causing problems.
You also can try to run "vwdexpress.exe /resetsettings" to reset VWD's setting or run "vwdexpress.exe /log <full path to log file>" to generate log file to troubleshoot this issue.
For more information, see http://blogs.msdn.com/astebner/archive/2005/11/11/491924.aspx
I look forward to receiving your test results.
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