A LNK2005 error occurs when the CRT library and MFC libraries are linked in the wrong order in Visual C++

MORE INFORMATION

When you use the MFC libraries, you must make sure that they are linked before the CRT library is linked. You can do this by making sure that every file in your project includes Msdev\Mfc\Include\Afx.h first, either directly (#include <Afx.h>) or indirectly (#include <Stdafx.h>). The Afx.h include file forces the correct order of the libraries, by using the #pragma comment (lib,"<libname>") directive.

If the source file has a .c extension, or the file has a .cpp extension but does not use MFC, you can create and include a small header file (Forcelib.h) at the top of the module. This new header makes sure that thelibrary search order is correct.

Visual C++ does not contain this header file. To create this file, follow these steps:

1. Open Msdev\Mfc\Include\Afx.h.
2. Select the lines between #ifndef _AFX_NOFORCE_LIBS and #endif //!_AFX_NOFORCE_LIBS.
3. Copy the selection to the Windows Clipboard.
4. Create a new text file.
5. Paste the contents of the Clipboard into this new file.
6. Save the file as Msdev\Mfc\Include\Forcelib.h.

Steps to Reproduce the Problem in Visual C++ .NET

1. Start Microsoft Visual Studio .NET.
2. On the File menu, point to New, and then click Project.
3. Click Visual C++ Projects under Project Types, and then click MFC Application under Templates.
4. In the Name text box, type Q148652.
5. In the Location text box, type C:\Test, and then click OK.
6. In the MFC Application Wizard dialog box, click Application Type.
7. Click Dialog based under Application type, and then click Use MFC in a static library under Use of MFC.
8. Click Finish.
9. In Solution Explorer, under Source Files select all the three .cpp files.
10. Right-click the three selected files, and then click Remove.
11. Right-click Source files, point to Add, and then click Add New Item.
12. Click C++ files under Templates. In the Name text box, type Aa. Click Open.
13. Paste the following code in the Aa.cpp file:

    int test(){new int; return 1;}

14. Right-click Source Files, point to Add, and then click Add Existing Item.
15. Select the following files:
    • Q148652.cpp
    • Q148652Dlg.cpp
    • stdafx.cpp
16. Click Open.
17. The files that you selected in step 15 appear under Source Files.
18. Select all four .cpp files under Source Files.
19. Right-click the four .cpp files that you selected, and then click Properties.
20. Expand Configuration Properties, and then expand C/C++.
21. Click Precompiled Headers.
22. Set the Create/Use Precompiled Header property to Not Using Precompiled Headers. Click OK.
23. On the Build menu, click Rebuild Solution.