We have a project named tigerenvelopes with the username tigerprivacy. It appears that there has been some mix up when SourceForge changed their servers.
If you go to http://tigerenvelopes.web.sourceforge.net/, you see the web pages for the project (as expected). But, when we logged in via this command:
sftp tigerprivacy@web.sourceforge.net there were no html files under userweb/htdocs...