When you’re urnning under x64 you have to affect 1 addition spot in the registry to disable this warning – which clearly should only be done by folks that know what they’re doing.

NOTE: affecting the registry can be harmful – do so at your own risk.

Windows Registry Editor Version 5.00

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\10.0\Debugger]
"DisableAttachSecurityWarning"=dword:00000001

[HKEY_CURRENT_USER\Software\Wow6432Node\Microsoft\VisualStudio\10.0\Debugger]
"DisableAttachSecurityWarning"=dword:00000001