14.04 - Ethernet Connection issues

I have a similar problem to this one:

Ethernet connection not working after installing Ubuntu 14.04 LTS

I also have a dual boot with windows 7 and ubuntu 14.04. My ethernet connection has always been fine in ubuntu. I recently booted to windows 7 for the first time, and connection was still fine. The problem came when I booted back into ubuntu, with no connection being picked up.

Unfortunately I can't post the diagnosis info since I can't connect the machine to the internet, but from what I can tell the only major difference is that when I run

sudo lshw -class bridge

my "driver" comes up as e1000e and not as "forcedeth".

Hence, when I try @ElderGeek's solution (as root in the recovery mode), the line

rmmod forcedeth

returns something like

ERROR: Forcedeth not currently loaded

most likely since that's not even a driver.

I imagine that the answer is probably just to instead try

rmmod e1000e

modprobe e1000e msi=0 msix=0

exit

but I don't want to run commands that I don't fully understand in case I break something.

(Although I suppose it wouldn't matter if it's booted into recovery mode?)

EDIT - additional information

 ~ $ lspci | grep Ethernet

    00:19.0 Ethernet controller: Intel Corporation Ethernet Connection I217-LM (rev 04) 

 ~ $ ifconfig eth0 


     eth0      Link
     encap:Ethernet  HWaddr 64:00:6a:4d:d0:dc  
               BROADCAST MULTICAST  MTU:1500  Metric:1
               RX packets:0 errors:0 dropped:0 overruns:0 frame:0
               TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
               collisions:0 txqueuelen:1000 
               RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
               Interrupt:20 Memory:f7d00000-f7d20000 

 ~ $ sudo lshw -class bridge  


     *-pci                   
            description: Host bridge
            product: 4th Gen Core Processor DRAM Controller
            vendor: Intel Corporation
            physical id: 100
            bus info: pci@0000:00:00.0
            version: 06
            width: 32 bits
            clock: 33MHz

            configuration: driver=hsw_uncore
            resources: irq:0
          *-pci
               description: PCI bridge
               product: Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller
               vendor: Intel Corporation
               physical id: 1
               bus info: pci@0000:00:01.0
               version: 06
               width: 32 bits

               clock: 33MHz
               capabilities: pci pm msi pciexpress normal_decode bus_master cap_list
               configuration: driver=pcieport
               resources: irq:26 ioport:e000(size=4096) 
     memory:f7c00000-f7cfffff ioport:e0000000(size=268435456)
          *-isa
               description: ISA bridge
               product: Q87 Express LPC Controller
               vendor: Intel Corporation
               physical id: 1f

               bus info: pci@0000:00:1f.0
               version: 04
               width: 32 bits
               clock: 33MHz
               capabilities: isa bus_master cap_list
               configuration: driver=lpc_ich latency=0
               resources: irq:0 

 ~ $ sudo lshw -class network 


      *-network DISABLED      
            description: Ethernet interface
            product: Ethernet Connection I217-LM
            vendor: Intel Corporation
            physical id: 19
            bus info: pci@0000:00:19.0
            logical name: eth0
            version: 04
            serial: 64:00:6a:4d:d0:dc
            size: 100Mbit/s

            capacity: 1Gbit/s
            width: 32 bits
            clock: 33MHz
            capabilities: pm msi bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
            configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=3.3.3-NAPI duplex=full firmware=0.13-4 latency=0 link=no multicast=yes port=twisted pair speed=100Mbit/s
            resources: irq:29 memory:f7d00000-f7d1ffff memory:f7d3d000-f7d3dfff ioport:f080(size=32) 

     ~ $ lsb_release -a

         No LSB modules are available. 

         Distributor ID:    Ubuntu Description: 
         Ubuntu 14.04.4 LTS 
         Release:   14.04 
         Codename:  trusty

So in the end I managed to solve the problem by adding the following lines to /etc/network/interfaces:

auto eth0
iface eth0 inet dhcp

(I believe this is essentially the same as clicking on the connections icon -> edit settings -> change the relevant interface setting)

The internet now works, the only minor snag is that the "connections" icon on the tab on the top of the page does not seem to recognise that there is a working connection.