I just installed Ubuntu on my laptop yesterday and it connected to the wireless fine. Then I took it to school, put it on their wired connection, downloaded some stuff, and now the wireless doesn't work.
At first it would detect networks, but not connect. I restarted it and now it can connect, but it acts like it doesn't have internet in the browser. Wired connection still works fine on it.
I know it isn't the network because my ipad is working on the wireless connection fine. I found another solution on here switching the security settings for the wireless, but this is the apartment's wireless so they have it open, and I won't be able to mess with it at all.
Here is lspci output:
00:00.0 Host bridge: Intel Corporation Core Processor DMI (rev 11)
00:03.0 PCI bridge: Intel Corporation Core Processor PCI Express Root Port 1 (rev 11)
00:08.0 System peripheral: Intel Corporation Core Processor System Management Registers (rev 11)
00:08.1 System peripheral: Intel Corporation Core Processor Semaphore and Scratchpad Registers (rev 11)
00:08.2 System peripheral: Intel Corporation Core Processor System Control and Status Registers (rev 11)
00:08.3 System peripheral: Intel Corporation Core Processor Miscellaneous Registers (rev 11)
00:10.0 System peripheral: Intel Corporation Core Processor QPI Link (rev 11)
00:10.1 System peripheral: Intel Corporation Core Processor QPI Routing and Protocol Registers (rev 11)
00:16.0 Communication controller: Intel Corporation 5 Series/3400 Series Chipset HECI Controller (rev 06)
00:1a.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 05)
00:1b.0 Audio device: Intel Corporation 5 Series/3400 Series Chipset High Definition Audio (rev 05)
00:1c.0 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 1 (rev 05)
00:1c.1 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 2 (rev 05)
00:1c.2 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 3 (rev 05)
00:1c.3 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 4 (rev 05)
00:1c.4 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 5 (rev 05)
00:1d.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 05)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev a5)
00:1f.0 ISA bridge: Intel Corporation Mobile 5 Series Chipset LPC Interface Controller (rev 05)
00:1f.2 SATA controller: Intel Corporation 5 Series/3400 Series Chipset 4 port SATA AHCI Controller (rev 05)
00:1f.3 SMBus: Intel Corporation 5 Series/3400 Series Chipset SMBus Controller (rev 05)
01:00.0 VGA compatible controller: NVIDIA Corporation GT218 [GeForce 310M] (rev a2)
01:00.1 Audio device: NVIDIA Corporation High Definition Audio Controller (rev a1)
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 05)
07:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8191SEvB Wireless LAN Controller (rev 10)
16:00.0 System peripheral: JMicron Technology Corp. SD/MMC Host Controller (rev 20)
16:00.2 SD Host controller: JMicron Technology Corp. Standard SD Host Controller (rev 20)
16:00.3 System peripheral: JMicron Technology Corp. MS Host Controller (rev 20)
16:00.4 System peripheral: JMicron Technology Corp. xD Host Controller (rev 20)
ff:00.0 Host bridge: Intel Corporation Core Processor QuickPath Architecture Generic Non-Core Registers (rev 04)
ff:00.1 Host bridge: Intel Corporation Core Processor QuickPath Architecture System Address Decoder (rev 04)
ff:02.0 Host bridge: Intel Corporation Core Processor QPI Link 0 (rev 04)
ff:02.1 Host bridge: Intel Corporation Core Processor QPI Physical 0 (rev 04)
ff:03.0 Host bridge: Intel Corporation Core Processor Integrated Memory Controller (rev 04)
ff:03.1 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Target Address Decoder (rev 04)
ff:03.4 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Test Registers (rev 04)
ff:04.0 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 0 Control Registers (rev 04)
ff:04.1 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 0 Address Registers (rev 04)
ff:04.2 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 0 Rank Registers (rev 04)
ff:04.3 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 0 Thermal Control Registers (rev 04)
ff:05.0 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 1 Control Registers (rev 04)
ff:05.1 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 1 Address Registers (rev 04)
ff:05.2 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 1 Rank Registers (rev 04)
ff:05.3 Host bridge: Intel Corporation Core Processor Integrated Memory Controller Channel 1 Thermal Control Registers (rev 04)
Update:
I re-installed Ubuntu 12.04 (I assumed I messed something up while toying with it) but it did not solve the problem. Eventually, I got it to work with my school's wireless internet (the default network settings were wrong), but the internet still doesn't work on my apartment's wifi (it has no security on it).
