Membership plugin. Download file throw 404, file not found.

Hi, I'm building a membership site. I have 2 access levels (free, paid). For the paid access, I add 'download' to the positive rules with the 'defaults' download group checked.

When I visit http://domain.dom/downloads/wp-content/uploads/2012/07/blank.pdf, I only get '404 — File not found.' message. Please explain why this error thrown?

FYI, I'm on membership plugin version 3.0.2.

Thanks.