新手提问，打开sln无法读取项目文件~~~~~~~

BIM文件夹中包括文件夹：BIM、DAL、COMMON、MODEL，每个文件夹下都有工程文件。在IIS中设置了虚拟路径指向BIM\BIM文件夹。BIM.sln文件打开后如下：
Microsoft Visual Studio Solution File, Format Version 8.00
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DAL", "DAL\DAL.csproj", "{831D5CC3-FA97-45A0-B1F2-A38D8E960258}"
ProjectSection(ProjectDependencies) = postProject
EndProjectSection
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Components", "Components\Components.csproj", "{65689C2B-66C8-45C8-8BC2-5BC0B9A79916}"
ProjectSection(ProjectDependencies) = postProject
EndProjectSection
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Common", "Common\Common.csproj", "{3F9710EB-860E-4841-B298-896E3FDE089C}"
ProjectSection(ProjectDependencies) = postProject
EndProjectSection
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "BIM", "http://localhost/BIM/BIM.csproj", "{54A2A8D4-072C-49D7-8045-993E1A791CE4}"
ProjectSection(ProjectDependencies) = postProject
EndProjectSection
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Model", "Model\Model.csproj", "{8130CE76-E48F-4539-9A48-E2956FA7B22C}"
ProjectSection(ProjectDependencies) = postProject
EndProjectSection
EndProject
Project("{4F174C21-8C12-11D0-8340-0000F80270F8}") = "SQL", "SQL\SQL.dbp", "{5D0E41B0-32EF-4A4A-ACB6-31C1890D4F05}"
ProjectSection(ProjectDependencies) = postProject
EndProjectSection
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "BLL", "BLL\BLL.csproj", "{4BCA6DFF-6268-4AB9-8CB1-8DE691D88483}"
ProjectSection(ProjectDependencies) = postProject
EndProjectSection
EndProjectvs打开sln，报：无法读取项目文件“BIM.csproj” 系统找不到指定的路径。
什么原因啊，试了多次了。