title: System.Data Doesn't Exist in Visual Studio 2010
body: <p>I have a red line under System.Data saying that "The type or namespace 'Data' does not exist in the namespace 'System' (are you missing an assembly reference?)." </p>
  
  <p>Thought I needed 4.5 .Net Framework, but I have another project that can use the namespace, so it is something with this project that I am using. </p>
  
  <p>I have seen other threads similar to mine, such as <a href="https://stackoverflow.com/questions/18419135/the-type-or-namespace-name-sqlite-does-not-exist-in-the-namespace-system-data">this</a>, but it isn't directly related to just system.data. It's trying to add a namespace beyond data, so there system.data namespace isn't the problem. Haven't seen any threads only related to just the system.data namespace. Any help would be appreciated. </p>