Ok a couple of weeks ago I started having some strange behavior in Visual Studio: Whenever I've been editing web.config in Visual Studio and then press the Ctrl-S key to save the file the web.config file closes. This is pretty annoying if you're working with the web.config file a lot as I do <s>...
Anyway, according to Omar Khan from Microsoft it turns out the problem is due to a bug in the ADO.NET Entity Framework Designer Tools, which I had installed shortly after installing the ASP.NET 3.5 Extensions that include the ADO.NET Entity framework. The tools are a seperate install from the ASP.NET 3.5 Extensions and they are responsible for providing the diagramming support in Visual Studio. Uninstalling just the Designer Tools solves the web.config issue. This will be fixed in future release but for the moment this particular issue is affecting me too much to leave the designer tools installed.
I've mentioned this in a previous post, but figured I'd repost it here in a more visible spot as a few people seem to have run into this same issue.
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