There is only one file type that uses the .VBHTML extension:
ASP.NET Razor Web Page
Visual Basic HTML Web file used by Razor, an ASP.NET view engine that generates webpages on a Microsoft IIS Web server; similar to a standard ASP.NET webpage (.ASP or .ASPX file), but uses slightly different syntax that offers new HTML templating features.
VBHTML files are executed by IIS Web server, which uses the Razor engine to generate a Web page that is sent to the client Web browser.
NOTE: VBHTML files are similar to .CSHTML (C# HTML) files, but use a slightly different syntax that is closer to the Visual Basic language.
Updated: June 23, 2011