Open your registry editor and create the following registry key and value:
Key:
HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\11.0\General\ SuppressUppercaseConversionValue:
REG_DWORD value: 1
For Windows 8 Express go to:
HKEY_CURRENT_USER\Software\Microsoft\VSWinExpress\11.0\GeneralFor Web Express go to:
HKEY_CURRENT_USER\Software\Microsoft\VSWDExpress\11.0\General
Here’s what it looks like before:

And here it is after the change:

Testato su Win 7 + VS2012 Ultimate
Trovato qui e qui.