When debug a ASP.NET Site, which is host in IIS, from Visual Studio 2012, VS stop working like this.
"Microsoft Visual Studio 2012 has stopped working"
Exception info: "System.AccessViolationException"
A work round to solve this problem. Go to IIS and open the advance setting of related Application Pool, then set the "Maximum Worker Process" to 1.
Root cause unknown. Thanks to this link
http://stackoverflow.com/questions/13189625/visual-studio-2012-crashes-everytime-i-try-to-debug-with-error-clr20r3