Unable to read the project file 'myapp.csproj'

I am getting below popup message when I try to open .sln file
" Unable to read the project file 'myapp.csproj' "
can any one help to solve this problem. i need this argent.

Open the project file via a text editor and see what's wrong. It's just an xml file.

Its not an Excel file , its a Microsoft visual studio solution file.
content in that file is below:
Microsoft Visual Studio Solution File, Format Version 9.00
# Visual Studio 2005
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SymphonyDataBroker", "SymphonyDataBroker.csproj", "{60B92088-D95C-48EE-807C-CC0F123B0A88}"
EndProject
Global
GlobalSection(SolutionConfigurationPlatforms) = preSolution
Debug|Any CPU = Debug|Any CPU
Release|Any CPU = Release|Any CPU
EndGlobalSection
GlobalSection(ProjectConfigurationPlatforms) = postSolution
{60B92088-D95C-48EE-807C-CC0F123B0A88}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
{60B92088-D95C-48EE-807C-CC0F123B0A88}.Debug|Any CPU.Build.0 = Debug|Any CPU
{60B92088-D95C-48EE-807C-CC0F123B0A88}.Release|Any CPU.ActiveCfg = Release|Any CPU
{60B92088-D95C-48EE-807C-CC0F123B0A88}.Release|Any CPU.Build.0 = Release|Any CPU
EndGlobalSection
GlobalSection(SolutionProperties) = preSolution
HideSolutionNode = FALSE
EndGlobalSection
EndGlobal

I know where the .sln extension stands for ;)

You are missing the myapp.csproj (or the location has changed), that's where the solution is complaining about. So, again, open the sln file in a text editor (for example notepad), and fix the problem.

I got the same error.
imported project file Microsoft.Silverlight.CSharp.targets not found.

this path to Microsoft.Silverlight.CSharp.targets wrong. i searched the file Microsoft.Silverlight.CSharp.targets in explorer and got the path.

then i opened the .csproj in wordpad and changed the path here

<Import Project="$(MSBuildExtensionsPath)\Microsoft\VisualStudio\v9.0\Silverlight\Microsoft.Silverlight.CSharp.targets" />

then it got loaded

Cheers!