Add in the system Path:

C:\Program Files (x86)\OpenCV-2.1.0\build\bin\Debug

Project->Project Property->Configuration Properties->VC++Directories ->Include Directories:

C:\Program Files (x86)\OpenCV-2.1.0\include\opencv.

Project->Project Property->Configuration Properties->VC++Directories ->Library Directories:

C:\Program Files (x86)\OpenCV-2.1.0\build\lib\Debug

Project->Project Property->Configuration Properties->Linker->Input:

cvaux210d.lib
highgui210d.lib
cv210d.lib
ml210d.lib
cxts210d.lib
cxcore210d.lib
opencv_ffmpeg210d.lib

Configuration of OpenCV2.1.0 with VS2010