The type or namespace name 'MyFeature.Class' could not be found in global namespace

Question

I am replacing the OOTB SharePoint 2010 People Picker Control with a custom People Picker.

There are 2 projects in my Solution. One that adds an application page and another that actually replaces People Picker.

Everything compiles without an error. Also, I use the Solution1 reference in Solution2 as I have some common classes that I'm re-using from Sol1 in Sol2. The Error occurs even if I do not use a reference of Sol1 in Sol2.

When I deploy it in Debug mode through VS2010. I am able to see the Custom Application Page (Uses SPPersisted Objects to store Custom Properties to Property Bag) and it works great.

But when I open the People Picker from the site, it throws

An error occurred during the compilation of the requested file, or one of its dependencies. The type or namespace name 'Custom_People_Picker_Control' could not be found in the global namespace (are you missing an assembly reference?).

I was expecting that it would hit my one of debug points in the People Picker Control Logic I have, but it doesn't and simply throws the error above.

I have checked it in GAC and both the dlls are deployed and version number also matches. Both solutions are compiled against .Net 3.5.

What might be missing?

Answer 1

Did you remember to include a import statement in your page?

<%@ Import Namespace="Solution2.Custom_People_Picker_Control" %>

Answer 2

Here is what i did in my FeatureEventReceiver + FeatureActivated Event

            string Asm_modificationName = string.Format(@"add[@assembly='{0}']", Assembly.GetExecutingAssembly().FullName);
            SPWebConfigModification Asm_modification = new SPWebConfigModification(Asm_modificationName, "configuration/system.web/compilation/assemblies");
            Asm_modification.Path = "configuration/system.web/compilation/assemblies";
            Asm_modification.Value = string.Format(@"<add assembly=""{0}"" />", Assembly.GetExecutingAssembly().FullName); ;
            Asm_modification.Owner = ownerID;
            Asm_modification.Sequence = 0;
            Asm_modification.Type = SPWebConfigModification.SPWebConfigModificationType.EnsureChildNode;
            webApp.WebConfigModifications.Add(Asm_modification);