Using MS Visual Studio 2010. Migrated a project up to .NET 4.0 probably 2 years ago and did significant coding on it. We don't actually need .NET 4.0, just wanted to keep up with the times. But now we need a rush release and do not want to include a .net upgrade on top of all other changes.
So, I changed all targets back to .NET 2.0. When I run, the first time that I hit the app.settings, I get an error "Unrecognized configuration section connectionStrings. (c:\Folder\Program.vshost.exe.Config line 12)"
If I switch back to .NET 4.0 it goes away.
I checked all references for a reference to a 4.0.0.0 system.* Nothing found.
I did a text search of *.cs and found files Settings.Designer.cs had a comment referencing it...
//------------------------------------------------------------------------------
// <auto-generated>
// This code was generated by a tool.
// Runtime Version:4.0.30319.18444
//
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
Any ideas where else to look?