Unable to add a reference to project '{0}'. The targets of Portable Library project '{0}' are not the same or compatible with the targets of the current Portable Library project.
A Portable Library project's targets can be changed via the Library tab in the project's properties.
Unable to add a reference to project '{0}'. The current project does not support references to Portable Library projects. ...
Unable to add a reference to project '{0}'. The current project's target framework is not one of or compatible with the target ...
Unable to add a reference to project '{0}'. The current project's target is not one of or compatible with the targets of ...
Unable to add a reference to project '{0}'. The target frameworks of Portable Library project '{0}' are not the same or compatible ...
Unable to add a reference to project '{0}'. The targets of Portable Library project '{0}' are not the same or compatible ...
Unable to add a service reference to the specified OData feed because WCF Data Services is not installed for this target ...
Unable to add references. There is no combination of framework targets that support all of the references you have selected. ...
Unable to add the specified project reference. The reference must be a Windows Phone project that targets the current or ...
Unable to add user '{0}' as a service user in Release Management Server for Team Foundation Server 2013. Contact your administrator. ...