2.Include SimpleTextIn.h in SimpleTextInEx.h because EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL is an extension of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL. 3.Include SimpleTextInEx.h in UefiSpec.h. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11612 6f19259b-4bc3-4df7-8a09-765794883524