Bug 331521

This is pretty old, but...

Any chance you still have the error, or are you still seeing this? If not, do
you remember how the mount read failed (as in, any reasonably way to reproduce?)
Thanks.

virt-manager-0.6.0-1.fc10.x86_64 on rawhide with all updates of today. If you install a new virtual machine and choose for a physical CD while there is none you'll get a backtrace:

Uncaught error validating input: 'NoneType' object has no attribute 'startswith'

Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/create.py", line 303, in forward
    if(self.validate(notebook.get_current_page()) != True):
  File "/usr/share/virt-manager/virtManager/create.py", line 953, in validate
    self._guest.installer.location = src
  File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 148, in set_location
    elif os.path.exists(os.path.abspath(val)) \
  File "/usr/lib64/python2.5/posixpath.py", line 402, in abspath
    if not isabs(path):
  File "/usr/lib64/python2.5/posixpath.py", line 49, in isabs
    return s.startswith('/')
AttributeError: 'NoneType' object has no attribute 'startswith'

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Moving to F10, I'll look into this.

Okay, a fix is pushed upstream:

http://hg.et.redhat.com/cgi-bin/hg-virt.cgi/applications/virt-manager--devel/rev/271f41b7218f

Moving to POST.

virt-manager-0.6.1-1.fc10 has been submitted as an update for Fedora 10.
http://admin.fedoraproject.org/updates/virt-manager-0.6.1-1.fc10

virt-manager-0.6.1-1.fc10 has been pushed to the Fedora 10 testing repository.  If problems still persist, please make note of it in this bug report.
 If you want to test the update, you can install it with 
 su -c 'yum --enablerepo=updates-testing update virt-manager'.  You can provide feedback for this update here: http://admin.fedoraproject.org/updates/F10/FEDORA-2009-2390

Fixed in virt-manager-0.6.1-3.fc10 which is in F10. Closing as CURRENTRELEASE.