IOError: CRC check failed (lp:#676767)

[Original report](https://bugs.launchpad.net/bugs/676767) created by **Lukas (l-niemeyer)**
```
NOTE FOR PEOPLE EXPERIENCING THIS PROBLEM:

The instructions at http://live.gnome.org/DejaDup/Help/Restore/WorstCase
seem to help people recover from this.  Duplicity works, but Deja Dup
doesn't.

Original report (edited for more brevity) below.

-----------------

Hi, I can't restore my backup, deja dup shows an error:

-----------------

DUPLICITY: ERROR 30 IOError
DUPLICITY: . Traceback (most recent call last):
DUPLICITY: .   File "/usr/bin/duplicity", line 1257, in <module>
DUPLICITY: .     with_tempdir(main)
DUPLICITY: .   File "/usr/bin/duplicity", line 1250, in with_tempdir
DUPLICITY: .     fn()
DUPLICITY: .   File "/usr/bin/duplicity", line 1204, in main
DUPLICITY: .     restore(col_stats)
DUPLICITY: .   File "/usr/bin/duplicity", line 539, in restore
DUPLICITY: .     restore_get_patched_rop_iter(col_stats)):
DUPLICITY: .   File "/usr/lib/python2.6/dist-
packages/duplicity/patchdir.py", line 522, in Write_ROPaths
DUPLICITY: .     ITR( ropath.index, ropath )
DUPLICITY: .   File "/usr/lib/python2.6/dist-packages/duplicity/lazy.py",
line 335, in __call__
DUPLICITY: .     last_branch.fast_process, args)
DUPLICITY: .   File "/usr/lib/python2.6/dist-packages/duplicity/robust.py",
line 37, in check_common_error
DUPLICITY: .     return function(*args)
DUPLICITY: .   File "/usr/lib/python2.6/dist-
packages/duplicity/patchdir.py", line 575, in fast_process
DUPLICITY: .     ropath.copy( self.base_path.new_index( index ) )
DUPLICITY: .   File "/usr/lib/python2.6/dist-packages/duplicity/path.py",
line 416, in copy
DUPLICITY: .     other.writefileobj(self.open("rb"))
DUPLICITY: .   File "/usr/lib/python2.6/dist-packages/duplicity/path.py",
line 591, in writefileobj
DUPLICITY: .     buf = fin.read(_copy_blocksize)
DUPLICITY: .   File "/usr/lib/python2.6/dist-
packages/duplicity/patchdir.py", line 200, in read
DUPLICITY: .     if not self.addtobuffer():
DUPLICITY: .   File "/usr/lib/python2.6/dist-
packages/duplicity/patchdir.py", line 221, in addtobuffer
DUPLICITY: .     self.buffer += fp.read()
DUPLICITY: .   File "/usr/lib/python2.6/dist-
packages/duplicity/tarfile.py", line 1338, in _readnormal
DUPLICITY: .     return self.fileobj.read(bytestoread)
DUPLICITY: .   File "/usr/lib/python2.6/dist-
packages/duplicity/dup_temp.py", line 204, in read
DUPLICITY: .     return self.fileobj.read(length)
DUPLICITY: .   File "/usr/lib/python2.6/gzip.py", line 219, in read
DUPLICITY: .     self._read(readsize)
DUPLICITY: .   File "/usr/lib/python2.6/gzip.py", line 284, in _read
DUPLICITY: .     self._read_eof()
DUPLICITY: .   File "/usr/lib/python2.6/gzip.py", line 304, in _read_eof
DUPLICITY: .     hex(self.crc)))
DUPLICITY: . IOError: CRC check failed 0xbfacd5c8L != 0xca281a1cL
DUPLICITY: .

** (deja-dup:4599): DEBUG: DuplicityInstance.vala:553: duplicity (4613)
exited with value 30

---------------------

Version of deja-dup and duplicity

deja-dup        16.0-0ubuntu1
duplicity       0.6.10-0ubuntu1

---------------

System: Ubuntu 10.04.1 LTS

I backed up the Data using Ubuntu 10.04 as well. Created the backup on an
external harddrive. Formated my harddisk today and reinstalled Ubuntu
10.04. Then I tried to restore the data.

Hope you can help me.
```
Original tags: restore

Story points: 30.0