How many clicks has this dialog eaten out of your life?
The idea for the warning is good because, you know, SECURITY. However, if you’re developing web apps or anything running in IIS, this gets old by the thousandth time you click the Attach button. It’s easy to turn off with an undocumented registry key. Make sure to shut down all instances of VS before changing this key as it will get overwritten on shutdown.
For Visual Studio 2015: HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\14.0\Debugger
For Visual Studio 2013: HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\12.0\Debugger
In the Debugger key, add a REG_DWORD value of DisableAttachSecurityWarning and set it to 1, and you now have one less click when you attach to a process.