Hi all,
Someone on the Kobo Facebook page was having problems uploading/opening a PDF file with password protection on it. I think one easy fix to this is to just remove the password altogether if you have Adobe Acrobat.
From the Adobe Support page:
In the open PDF, do one of the following:
* Select Advanced > Security > Remove Security.
* In the Security tab of the Document Properties dialog box, choose No Security from the Security Method menu.
Just thought I'd share this for reference
If anyone has any other solutions please post them here!