Are you trying to build a SQL Server database project and getting   The imported project "C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v10.0\SSDT\Microsoft.Data.Tools.Schema.SqlTasks.targets" was not found. Confirm that the path in the declaration is correct, and that the file exists on disk. We had this recently when trying to build one SSDT solution but not when building another.   Checking the build agent the error was correct that file didn’t exist...(read more)

http://sqlblogcasts.com/blogs/simons/archive/2014/07/22/the-imported-project-quot-c-program-files-x86-msbuild-microsoft-visualstudio-v10-0-ssdt-microsoft-data-tools-schema-sqltasks-targets-quot-was-not-found-confirm-that-the-path-in-the-lt-import-gt-declaration-is-correct-and-that.aspx