Did you read the links I gave you? They discuss localization in great length. First, if you are authoring the original forms in Spanish and it is in that locale that all your code is contained, then use the NeutralResourcesLanguageAttribute and specify the appropriate culture. Second, try going back to the "default" culture (actually the neutral culture) in your form designer and compile again. VS.NET might thing that you're trying to compile the English satellite assembly as the primary assembly. Second, show hidden files in your project. Look at the ResX files. If you use VS.NET's designers, these will be hidden under forms. If your form source file is named MyForm.cs, then you should have a MyForm.resx (the neutral language) and MyForm.en.resx or MyForm.en-US.resx.
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