ploneintranet-attachments-error

2015-03-25 15:42:52 INFO collective.documentviewer Running command /usr/local/bin/docsplit pdf /tmp/admin-20150325144236683988-sitibt/dump.dat --output /tmp/admin-20150325144236683988-sitibt
2015-03-25 15:42:54 INFO collective.documentviewer Finished Running Command /usr/local/bin/docsplit pdf /tmp/admin-20150325144236683988-sitibt/dump.dat --output /tmp/admin-20150325144236683988-sitibt
2015-03-25 15:42:54 WARNING ploneintranet.attachments.browser.upload Could not get previews for attachment: admin-20150325144236683988-sitibt.zip, Exception: Error converting to pdf
2015-03-25 15:42:54 ERROR root could not scale "<plone.namedfile.file.NamedBlobFile object at 0x7f36fbde15f0>" of 'http://localhost:8080/Plone/test-yasaaaa/++attachments++default/admin-20150325144236683988-sitibt.zip'
Traceback (most recent call last):
  File "/home/jack/dev/buildout-cache/python2.7/eggs/plone.namedfile-3.0.1-py2.7.egg/plone/namedfile/scaling.py", line 258, in create
    **parameters)
  File "/home/jack/dev/buildout-cache/python2.7/eggs/plone.scale-1.3.4-py2.7.egg/plone/scale/scale.py", line 31, in scaleImage
    image = PIL.Image.open(image)
  File "/home/jack/dev/buildout-cache/python2.7/eggs/Pillow-2.3.0-py2.7-linux-x86_64.egg/PIL/Image.py", line 2025, in open
    raise IOError("cannot identify image file")
IOError: cannot identify image file
2015-03-25 15:42:54 ERROR ploneintranet.attachments.browser.upload Preview url generation failed
Traceback (most recent call last):
  File "/home/jack/dev/plone/ploneintranet/src/ploneintranet/attachments/browser/upload.py", line 50, in get_image_thumbs_urls
    urls = [images.scale(image_field, 'preview').absolute_url()]
AttributeError: 'NoneType' object has no attribute 'absolute_url'