When attempting to update or upload an article or folio from within the Folio Builder panel, the process fails with the error, "The upload has failed. [svr.Unknown]"
Ensure that the complete path to all InDesign files and related assets (images, movies, sounds) and their file names does not contain any characters outside of the printable characters of the 7-bit ASCII range. This should include the full path, for example:
\Users\username\desktop\client ABC\November 2011 folio\Article 12 Dining out\12_Dining_out_v.indd
\Users\username\desktop\client ABC\November 2011 folio\Article 12 Dining out\Links\Panorama\pan001.jpg
C:/Users/username/desktop/client ABC/November 2011 folio/Article 12 Dining out/12_Dining_out_v.indd
C:/Users/username/desktop/client ABC/November 2011 folio/Article 12 Dining out/Links/Panorama/pan001.jpg
Adobe hopes to address this in a future update to the Folio Producer service and/or the Folio Builder panel.
For more information on ASCII printable characters, see http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters