你好我想用 vc 11 构建 leptonica 库所以我下载了这个 leptonica vs2008 项目
并尝试用我的 vs2012 打开它，解决方案开始升级并显示消息：
One-way upgrade
Visual Studio will automatically make functional changes to the following projects in order to open them. You will not be able to open these projects in the version of Visual Studio in which they were originally created.
- liblept168, "C:\Lept\vs2008-1.68\vs2008\leptonica.vcproj"
- ioformats_reg, "C:\Lept\vs2008-1.68\vs2008\prog_projects\ioformats_reg\ioformats_reg.vcproj"
- leptonica, "C:\Lept\vs2008-1.68\vs2008\leptonica.sln"
No changes required
These projects can be opened in this version of Visual Studio without changing them. They will continue to open in Visual Studio 2010 SP1 and in this version of Visual Studio.
- prog_files, "prog_files"
- prog_projects, "prog_projects"
- Regression Test, "Regression Test"
- Test, "Test"
- Utility, "Utility"
- liblept Helper, "liblept Helper"
- Example, "Example"
- ByType, "ByType"
- ByFilename, "ByFilename"
- ByCategory, "ByCategory"
- Exploration, "Exploration"
- Basic Box, Boxa and Boxaa Functions, "Basic Box, Boxa and Boxaa Functions"
- Basic Image Operations, "Basic Image Operations"
- Basic Pix Array Functions, "Basic Pix Array Functions"
- Basic Pix Functions, "Basic Pix Functions"
- Colormap Utilities and Related Operations, "Colormap Utilities and Related Operations"
- Connected Components in Binary Images, "Connected Components in Binary Images"
- Formatted IO, "Formatted IO"
- Fundamental Data Structures for Computation, "Fundamental Data Structures for Computation"
- Image Display, "Image Display"
- Image Morphology, "Image Morphology"
- Image Operations With Filling, "Image Operations With Filling"
- Image Quantization, Depth Conversion, "Image Quantization, Depth Conversion"
- Image Scaling, "Image Scaling"
- Line Graphics and Special Output, "Line Graphics and Special Output"
- Low-level Pixel Access, "Low-level Pixel Access"
- Misc, "Misc"
- Other Geometric Image Transformations, "Other Geometric Image Transformations"
- Postscript, "Postscript"
- Printing, "Printing"
- Specialized Document Image Processing, "Specialized Document Image Processing"
- Specialized Image Filters, "Specialized Image Filters"
在传递所有项目文件后，解决方案已加载，但 2 个项目未能加载并出现以下错误：
莱普托尼卡：
leptonica.vcproj: The item type 'None' is not supported by this project item provider. Parameter name: itemType
Error leptonica.vcproj: Project upgrade failed.
Warning leptonica_versionnumbers.vsprops: Attribute 'ProjectType' of 'leptonica_versionnumbers' is not supported in this version and has been removed during conversion.
Warning leptonica_versionnumbers.vsprops: Attribute 'Version' of 'leptonica_versionnumbers' is not supported in this version and has been removed during conversion.
Warning leptonica.vcproj: VCWebServiceProxyGeneratorTool is no longer supported. The tool has been removed from your project settings.
Warning leptonica.vcproj: Attribute 'Detect64BitPortabilityProblems' of 'VCCLCompilerTool' is not supported in this version and has been removed during conversion.
Warning leptonica.vcproj: Attribute 'Detect64BitPortabilityProblems' of 'VCCLCompilerTool' is not supported in this version and has been removed during conversion.
Warning leptonica.vcproj: Attribute 'Detect64BitPortabilityProblems' of 'VCCLCompilerTool' is not supported in this version and has been removed during conversion.
Warning leptonica.vcproj: Attribute 'Detect64BitPortabilityProblems' of 'VCCLCompilerTool' is not supported in this version and has been removed during conversion.
和 - ioformats_reg：
prog_projects\ioformats_reg\ioformats_reg.vcproj: The item type 'None' is not supported by this project item provider. Parameter name: itemType
Error prog_projects\ioformats_reg\ioformats_reg.vcproj: Project upgrade failed.
Warning prog_projects\ioformats_reg\ioformats_reg.vcproj: VCWebServiceProxyGeneratorTool is no longer supported. The tool has been removed from your project settings.
还有 ..\vs2008\leptonica.vcproj：
Error: The following error has occurred during XML parsing: File: C:\Lept\vs2008-1.68\vs2008\leptonica.vcproj Line: 1069 Column: 0 Error Message:
Parameter is incorrect. The file 'C:\Lept\vs2008-1.68\vs2008\leptonica.vcproj' has failed to load.
..\ioformats_reg\ioformats_reg.vcproj：
Error : The following error has occurred during XML parsing: File: C:\Lept\vs2008-1.68\vs2008\prog_projects\ioformats_reg\ioformats_reg.vcproj
Line: 376 Column: 0 Error Message: Parameter is incorrect.
The file 'C:\Lept\vs2008-1.68\vs2008\prog_projects\ioformats_reg\ioformats_reg.vcproj' has failed to load.
我查看了 leptonica.vcproj 但在第 1069 行只有空白空间，它是文件中的最后一行，它是空的。我也没有在这个文件中找到任何“itemType”字符串。与文件 ioformats_reg.vcproj 相同。
我该如何解决这个错误？