Description of problem:
i tried to install fedora 19 using usb.
a message unknown error occured comes and installation stops

Version-Release number of selected component:
anaconda-19.30.13-1.fc19.x86_64

The following was filed automatically by anaconda:
anaconda 19.30.13-1 exception report
Traceback (most recent call first):
  File "/usr/lib64/python2.7/site-packages/pyanaconda/nm.py", line 159, in nm_device_property
    raise UnknownDeviceError(name, e)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/nm.py", line 212, in nm_device_type
    return nm_device_property(name, "DeviceType")
  File "/usr/lib64/python2.7/site-packages/pyanaconda/nm.py", line 194, in nm_device_type_is_ethernet
    return nm_device_type(name) == NetworkManager.DeviceType.ETHERNET
  File "/usr/lib64/python2.7/site-packages/pyanaconda/network.py", line 309, in dumpMissingDefaultIfcfgs
    if not nm.nm_device_type_is_ethernet(devname):
  File "/usr/lib64/python2.7/site-packages/pyanaconda/network.py", line 893, in networkInitialize
    if dumpMissingDefaultIfcfgs():
  File "/sbin/anaconda", line 1038, in <module>
    networkInitialize(ksdata)
UnknownDeviceError: UnknownDeviceError('ttyUSB0', GError('GDBus.Error:org.freedesktop.NetworkManager.UnknownDevice: No device found for the requested iface.',))

Additional info:
cmdline:        /usr/bin/python  /sbin/anaconda --liveinst --method=livecd:///dev/mapper/live-osimg-min --lang en_US.UTF-8
cmdline_file:   BOOT_IMAGE=/syslinux/vmlinuz0 root=live:LABEL=LIVE ro rd.live.image quiet rhgb
executable:     /sbin/anaconda
hashmarkername: anaconda
kernel:         3.9.5-301.fc19.x86_64
product:        Fedora
release:        Fedora release 19 (Schrödinger’s Cat)
type:           anaconda
version:        19