Sounds like bug. Lets dig in.
First, stop Network Manager: sudo service network-manager stop
Then, plug in the cable and bring up the interface sudo ifconfig eth0 up and tell it to ask for a new dhcp lease sudo dhclient eth0 (I'm guessing it's eth0, if not use the right name)
Did it work? If so, file a bug on Network Manager: ubuntu-bug -p network-manager
If not, try reloading the network driver. This should simulate a reboot to the ethernet port. To find out your driver, look in /etc/udev/rules.d/70-persistent-net.rules You'll see some bits like:
# PCI device 0x10ec:0x8136 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:f1:4c:01:94:3e", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
Finding the one that matches your interface's name, look at what's in the parentheses where mine says r8169. That's your module's name.
sudo modprobe -r r8169 && sudo modprobe r8169
(replacing r8169 with your module's name) Try the dhclient step again. If that worked, I suspect it's a kernel bug. ubuntu-bug -p linux
I seem to have found the solution.
I deleted all the previous connections, deleted the configuration file from /etc/network created by pppoeconf and rebooted. Then I set up the wired connection (Automatic ethernet) using the static addresses but made sure it didn't have "connect automatically" checked in the configuration dialog. Then I created a DSL connection, but of all the settings, I only filled in the user name, service name and password for it. I checked "available to all users" and closed the settings dialog. Then from the "connections" applet on the panel, clicked the connection name. And it connected and worked.
Nevertheless, after a couple of reboots, I'm noticing that sometimes it won't connect on the first "click". It'll show notification "Connection established" but I won't have internet access. So I need to disconnect and retry a few times, and eventually it works.
Update: I forgot to mention - I had to set the MTU to 1452 as well.
Best Answer
Another option is to try imagemagick convert utility,Imagemagic can be easily installed using software center or synaptic.
Since the document is scanned it should be a bitmap which imagemagick can handle, only the version of the .cdr would be a concern, you did not mention the version of the cdr file so you may just try imagemagick, at your terminal in the directory where the .cdr file is located, run the convert utility like this;
this will convert the .cdr image called image.cdr to a .png image called image.png file that you can easily use, probably vectorize by tracing in inkscape if you wish.
See the imagemagic documentation on the convert utility if more control over the output is needed. hope the output is satisfactory.