update-manager doesn't start after a recovery

I have an Asus eeepc 701, it runs Ubuntu 10.04 without problems, but it has worked a lot so the internal SSD needed a format (too many errors on boot, boot was impossible).
No problems I was awarded about this and I restored the disk from a fresh backup, everything ok, in 15 minutes I formatted the disk from a live usb and restored the disk.
But now the update-manager gives this error:

$ update-manager
Traceback (most recent call last):
  File "/usr/bin/update-manager", line 32, in <module>
    from UpdateManager.UpdateManager import UpdateManager
  File "/usr/lib/python2.6/dist-packages/UpdateManager/UpdateManager.py", line 64, in <module>
    import GtkProgress
  File "/usr/lib/python2.6/dist-packages/UpdateManager/GtkProgress.py", line 34, in <module>
    class GtkOpProgress(apt.OpProgress):
AttributeError: 'module' object has no attribute 'OpProgress'
$

The backup copy was made with a rsync command on an external device and restore has been made with a
sudo cp -ax /backup/device/* /mnt/sda1/

How can I fix that error?