请问如何让不是precompile的工程变成precompile

我有一个project原来不是precomile的，现在我想要变成precompile,我做了如下的尝试，但没有成功，请问什么原因？
1。 增加stdafx.h和stdafx.cpp两个文件
2。 让project中所有的工程都#include "stdafx.h"
3. project property中选择Use precompile

-------------尝试 1------------------
rebuild project 得到错误如下：
1>------ Rebuild All started: Project: test6, Configuration: Debug Win32 ------
1>Deleting intermediate and output files for project 'test6', configuration 'Debug|Win32'
1>Compiling...
1>stdafx.cpp
1>e:\yanwei\work\cpp\testprecompile\test6\source\stdafx.cpp(5) : error C2859: e:\yanwei\work\cpp\testprecompile\test6\test6\debug\vc80.pdb is not the pdb file that was used when this precompiled header was created, recreate the precompiled header.
1>e:\yanwei\work\cpp\testprecompile\test6\source\stdafx.cpp(5) : error C2859: e:\yanwei\work\cpp\testprecompile\test6\test6\debug\vc80.idb is not the idb file that was used when this precompiled header was created, recreate the precompiled header.
1>test6.cpp
1>e:\yanwei\work\cpp\testprecompile\test6\source\test6.cpp(4) : error C2859: e:\yanwei\work\cpp\testprecompile\test6\test6\debug\vc80.pdb is not the pdb file that was used when this precompiled header was created, recreate the precompiled header.
1>e:\yanwei\work\cpp\testprecompile\test6\source\test6.cpp(4) : error C2859: e:\yanwei\work\cpp\testprecompile\test6\test6\debug\vc80.idb is not the idb file that was used when this precompiled header was created, recreate the precompiled header.
1>Generating Code...
1>Build log was saved at "file://e:\yanwei\work\Cpp\testprecompile\test6\test6\Debug\BuildLog.htm"
1>test6 - 4 error(s), 0 warning(s)
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

就算我先编译stdafx.cpp也是上面的错误。

-------------尝试 2------------------
把debug目录删除,rebuild
1>------ Rebuild All started: Project: test6, Configuration: Debug Win32 ------
1>Deleting intermediate and output files for project 'test6', configuration 'Debug|Win32'
1>Compiling...
1>stdafx.cpp
1>e:\yanwei\work\cpp\testprecompile\test6\source\stdafx.cpp(5) : fatal error C1083: Cannot open precompiled header file: 'Debug\test6.pch': No such file or directory
1>test6.cpp
1>e:\yanwei\work\cpp\testprecompile\test6\source\test6.cpp(4) : fatal error C1083: Cannot open precompiled header file: 'Debug\test6.pch': No such file or directory
1>Generating Code...
1>Build log was saved at "file://e:\yanwei\work\Cpp\testprecompile\test6\test6\Debug\BuildLog.htm"
1>test6 - 2 error(s), 0 warning(s)
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

我把use precompile改为create precompile,rebuild这会倒是编译通过了,但再次改回use precompile还是和尝试1一样的错误.
多谢.