Tried opening the sln workspace file, spitting out things like:
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Microsoft Development Environment
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Unable to read the project file 'VisualOgreCore.csproj'. The file 'G:\tempprojs\OGRE Studio\Core\VisualOgreCore\VisualOgreCore.csproj' is not a valid project file. The project file is missing the 'VisualStudioProject' section.
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OK
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And the file is not empty, but it is in an unfamilier format, but then again I only know the vcproj format...