No Wifi - “Activation of network connection failed” Ubuntu 16.04 & 18.04

Question

I'm looking for some help with my Ubuntu laptop. I have an Intel Wireless 8260 card in my laptop that is unable to connect to any network. I've tried an Edimax USB WiFi adapter but get the exact same result. I've tried WPA2,WEP and open networks without any luck. This problem started with Ubuntu 16.04 and I was unable to resolve it, but I wanted to try out 18.04 and I was hoping it would resolve itself with the update. Every network adapter or wireless network I've tried has given me the same result. The only feedback I get is:

Activation of network connection failed

I do not have an Ethernet port on my laptop to try so I'm stuck without internet on that device.

If anyone has some suggestions, I'd appreciate it. Here is some preliminary information from the laptop:

sudo lshw -C network
  *-network                 
       description: Wireless interface
       product: Wireless 8260
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: wlp2s0
       version: 3a
       serial: e4:b3:18:3e:a4:a9
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=iwlwifi driverversion=4.15.0-20-generic firmware=34.0.1 latency=0 link=no multicast=yes wireless=IEEE 802.11
       resources: irq:135 memory:ddc00000-ddc01fff

iwconfig
    lo        no wireless extensions.

    wlp2s0    IEEE 802.11  ESSID:off/any  
              Mode:Managed  Access Point: Not-Associated   Tx-Power=22 dBm   
              Retry short limit:7   RTS thr:off   Fragment thr:off
              Power Management:on


lspci -nnk | grep -iA3 net
    02:00.0 Network controller [0280]: Intel Corporation Wireless 8260 [8086:24f3] (rev 3a)
    Subsystem: Intel Corporation Wireless 8260 [8086:0050]
    Kernel driver in use: iwlwifi
    Kernel modules: iwlwifi

rfkill list all
    1: dell-wifi: Wireless LAN
        Soft blocked: no
        Hard blocked: no
    2: dell-bluetooth: Bluetooth
        Soft blocked: yes
        Hard blocked: no
    3: phy0: Wireless LAN
        Soft blocked: no
        Hard blocked: no

dmesg | grep iwl
    [    3.237992] iwlwifi 0000:02:00.0: enabling device (0000 -> 0002)
    [    3.250564] iwlwifi 0000:02:00.0: loaded firmware version 34.0.1 op_mode iwlmvm
    [    3.276885] iwlwifi 0000:02:00.0: Detected Intel(R) Dual Band Wireless AC 8260, REV=0x208
    [    3.360425] iwlwifi 0000:02:00.0: base HW address: e4:b3:18:3e:a4:a9
    [    3.487355] ieee80211 phy0: Selected rate control algorithm 'iwl-mvm-rs'
    [    3.488961] iwlwifi 0000:02:00.0 wlp2s0: renamed from wlan0

Update: I was able to manually add an IP, Subnet and Gateway to successfully connect to my local network, still no internet and not an ideal solution but may provide a hint, possibly DHCP related?

Update 2: Thanks to a hint from @chili555, after I manually set the DNS server and was able to connect to the internet. So that'll at least let me get online to try to update packages, etc. Still DHCP related?

I can run any additional commands for more information. Thank you!

Solved: Solution was to update my clock, it was set to 2118 that made DHCP not work. After updating to the proper time, DHCP began to work as expected.

Answer 1

The issue was that my clock was set 2118 (100 years in the future). For whatever reason, this did not allow DHCP to work. I was able to get online using manual IP address assignment with the help of @chili555 which made me realize all website SSL certificates were expired, and led me to figure out the clock issue. Thanks again @chili555.