cant install software from center of ubuntu. And appears a message for few seconds and dissapears org.debian.apt.install-packages

Could you please provide the complete error message?

For me,

An unhandlable error occured

There seems to be a programming error in aptdaemon, the software that allows you to install/remove software and to perform other package management related tasks. Please report this error at http://launchpad.net/aptdaemon/+filebug and retry.

Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 765, in simulate
    return self._simulate_helper(trans, status_path)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 837, in _simulate_helper
    deb = apt.debfile.DebPackage(trans.kwargs["path"], self._cache)
  File "/usr/lib/python2.6/dist-packages/apt/debfile.py", line 57, in __init__
    self.open(filename)
  File "/usr/lib/python2.6/dist-packages/apt/debfile.py", line 66, in open
    self._debfile = apt_inst.DebFile(open(self.filename))
UnicodeEncodeError: 'ascii' codec can't encode character u'\xe9' in position 15: ordinal not in range(128)

that's exactly wats happening to me to! see mine
There seems to be a programming error in aptdaemon, the software that allows you to install/remove software and to perform other package management related tasks. Please report this error at http://launchpad.net/aptdaemon/+filebug and retry.
Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 768, in simulate
    return self._simulate_helper(trans, status_path)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 936, in _simulate_helper
    return depends, status, self._cache.required_download, \
  File "/usr/lib/python2.6/dist-packages/apt/cache.py", line 218, in required_download
    pm.get_archives(fetcher, self._list, self._records)
SystemError: E:I wasn't able to locate file for the lib32v4l-0 package. This might mean you need to manually fix this package.

To Michael, Your error is almost exactly like my error. I am an Ubuntu n00b and have no clue how to fix this!
Anyone out there able to help fix this error?

Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 768, in simulate
    return self._simulate_helper(trans, status_path)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 936, in _simulate_helper
    return depends, status, self._cache.required_download, \
  File "/usr/lib/python2.6/dist-packages/apt/cache.py", line 218, in required_download
    pm.get_archives(fetcher, self._list, self._records)
SystemError: E:I wasn't able to locate file for the libxine1-misc-plugins package. This might mean you need to manually fix this package.

i'm running ubuntu10.10 and i have the same problem.
is it any solution?