[support] (no subject)

[JvR O]

I have just tried to update drupal 8 beta2 to drupal 8 beta 3

I have received this error.
Any sugestion?

Thank you.
Regards.

drush pm-update projects drupal-8.0.0-beta3
Update information last refreshed: Wed, 11/12/2014 - 17:30
 Name      Installed Version  Proposed version  Message
 Drupal    8.0.0-dev          8.0.0-dev         Specified version available
 projects  Unknown            Unknown           Specified project not found


Code updates will be made to drupal core.
WARNING:  Updating core will discard any modifications made to Drupal core
files, most noteworthy among these are .htaccess and robots.txt.  If you
have made any modifications to these files, please back them up before
updating so that you can re-create your modifications in the updated
version of the file.
Note: Updating core can potentially break your site. It is NOT recommended
to update production sites without prior testing.

Do you really want to continue? (y/n): y
copy(): Filename cannot be empty
drush.inc:736
[warning]
Unable to download  to /home/anubis/public_html
from
[error]
Updating project drupal failed. Attempting to roll back to previously
installed
version.                                                            [error]
Backups were restored successfully.
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