I've installed Ubuntu 12.04 on a Dell Inspiron 1545 and I cannot access the internet. On the menu, Wired says the cable is unplugged and Wireless cannot find any network available.
The laptop comes with a Dell Wireless 1397 WLAN MiniCard.
I did try to connect using an Ethernet cable. When I went to System Settings -> Networks there was no list of connections and at the top it said "the cable is unplugged".
I found similar questions about problems with wireless connection and one of the answers was to connect with a cable and download a driver, that's why I tried wired connection first.
I also found recommendations to use
sudo apt-get install --reinstall bcmwl-kernel-source
or
sudo apt-get purge bcmwl-kernel-source
as a first step of fixing the problem. When I typed any of these commands I got as response that the package was not found.
after running lspci | grep Network the output is:
0c:00.0 Network controller: Broadcom Corporation BCM4312 802.11/g LP-PHY (rev 01)
Below I paste the commands I ran and the output
cat /etc/lsb-release; uname -a
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=12.04
DISTRIB_CODENAME=precise
DISTRIB_DESCRIPTION="Ubuntu 12.04.3 LTS"
Linux User 3.8.0-29-generic #42~precise1-Ubuntu SMP Wed Aug 14 16:19:23 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
lspci -nnk | grep -iA2 net
0c:00.0 Network controller [0280]: Broadcom Corporation BCM4312 802.11b/g LP-PHY [14e4:4315] (rev 01)
Subsystem: Dell Wireless 1397 WLAN Mini-Card [1028:000c]
Kernel driver in use: b43-pci-bridge
iwconfig
lo no wireless extensions.
lsmod
Module Size Used by
nls_iso8859_1 12713 1
bnep 18258 2
rfcomm 47864 0
bluetooth 247024 10 bnep,rfcomm
joydev 17613 0
parport_pc 28284 0
ppdev 17113 0
snd_hda_codec_idt 71153 1
uvcvideo 82214 0
videobuf2_core 40785 1 uvcvideo
b43 392109 0
videodev 130053 2 uvcvideo,videobuf2_core
videobuf2_vmalloc 13056 1 uvcvideo
videobuf2_memops 13202 1 videobuf2_vmalloc
mac80211 630977 1 b43
cfg80211 525244 2 b43,mac80211
snd_hda_intel 44339 3
snd_hda_codec 141716 2 snd_hda_codec_idt,snd_hda_intel
snd_hwdep 13668 1 snd_hda_codec
snd_pcm 102477 2 snd_hda_intel,snd_hda_codec
snd_seq_midi 13324 0
snd_rawmidi 30417 1 snd_seq_midi
coretemp 13596 0
i915 620421 3
snd_seq_midi_event 14899 1 snd_seq_midi
snd_seq 61930 2 snd_seq_midi,snd_seq_midi_event
mac_hid 13253 0
gpio_ich 13526 0
snd_timer 29989 2 snd_pcm,snd_seq
dell_wmi 12681 0
drm_kms_helper 49597 1 i915
sparse_keymap 13890 1 dell_wmi
snd_seq_device 14497 3 snd_seq_midi,snd_rawmidi,snd_seq
psmouse 97873 0
dell_laptop 17425 0
drm 287564 4 i915,drm_kms_helper
microcode 23017 0
dcdbas 14449 1 dell_laptop
serio_raw 13215 0
lpc_ich 17144 0
i2c_algo_bit 13564 1 i915
snd 69533 15 snd_hda_codec_idt,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device
bcma 41244 1 b43
video 19652 1 i915
soundcore 12680 1 snd
snd_page_alloc 18798 2 snd_hda_intel,snd_pcm
wmi 19256 1 dell_wmi
lp 17799 0
parport 46562 3 parport_pc,ppdev,lp
ums_realtek 18256 0
usb_storage 61749 2 ums_realtek
ahci 25879 2
libahci 31606 1 ahci
ssb 57842 1 b43
