One of my VS 2008 projects shows several warning lines in the Output window like this:
Consider app.config remapping of assembly "System.Windows.Forms, Culture=neutral, PublicKeyToken=969db8053d3322ac, Retargetable=Yes" from Version "1.0.5000.0" [] to Version "3.5.0.0" [C:\Program Files (x86)\Microsoft.NET\SDK\CompactFramework\v3.5\WindowsCE\System.Windows.Forms.dll] to solve conflict and get rid of warning.
...and yet there is no app.config file for this project. What does it really want?