You get this error when building your application in Iron Speed Designer:
Unable to edit menu component: Failed to parse layout file XXX.html. The relativeFileName cannot nothing or empty.
There is an error in your page’s GEN or HTML tags. For example, there may be a <GEN: > tag with a mismatched or missing < /GEN > closing tag.
If you add something that Iron Speed Designer does not know about, it simply 'ignores' it when updating your application; Iron Speed Designer will pass it through to your application’s ASPX page.
Part VII: Troubleshooting Applications
Application Generation and Compilation Error Messages