Edocman installation error

I dowloaded the edocman_unzip file. When I try to install this file - with the extension manager joomla - 1.7 I get the error:

JFolder: :files: Path is not a folder. Path: /.....................
JFolder: :folder: Path is not a folder. Path: /.....................
JFolder: :files: Path is not a folder. Path: /.....................
JInstaller: :Install: Cannot find Joomla XML setup file

Do I have to unpack the file first? but when I try to unpack I get the message 'no archieves found'

What is the problem?

I received a new zip file by email. It seems that my error was caused because the first received edocman_unzip file was damaged. The new sent package contained the correct files and I could install them as usual.

Thank you Tuan.