The Ubuntu Software Centre tool can no longer add or remove software and can no longer access the internet - even though all other applications can.

Can you give the output of:

sudo lshw -C network; lsb_release -a; ifconfig

How do you connect to the web? wired? Wireless? 3G?

As requested herewith is the output from sudo lshw -C network; lsb_release -a; ifconfig

  *-network
       description: Ethernet interface
       product: Atheros Communications
       vendor: Atheros Communications
       physical id: 0
       bus info: pci@0000:09:00.0
       logical name: eth0
       version: c0
       serial: bc:ae:c5:e4:ec:f1
       size: 100Mbit/s
       capacity: 1Gbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress vpd bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=atl1c driverversion=1.0.1.0-NAPI duplex=full firmware=N/A ip=10.1.1.2 latency=0 link=yes multicast=yes port=twisted pair speed=100Mbit/s
       resources: irq:56 memory:fb600000-fb63ffff ioport:c000(size=128)
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 11.04
Release: 11.04
Codename: natty
eth0 Link encap:Ethernet HWaddr bc:ae:c5:e4:ec:f1
          inet addr:10.1.1.2 Bcast:10.255.255.255 Mask:255.0.0.0
          inet6 addr: fe80::beae:c5ff:fee4:ecf1/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:1728 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1599 errors:0 dropped:0 overruns:0 carrier:1
          collisions:0 txqueuelen:1000
          RX bytes:1709355 (1.7 MB) TX bytes:267037 (267.0 KB)
          Interrupt:56

lo Link encap:Local Loopback
          inet addr:127.0.0.1 Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING MTU:16436 Metric:1
          RX packets:16 errors:0 dropped:0 overruns:0 frame:0
          TX packets:16 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:960 (960.0 B) TX bytes:960 (960.0 B)

I have a direct connection (wired) to the web.

Run;

gksudo gedit /etc/resolv.conf

delete all the text and add these 2 lines:

nameserver 8.8.8.8
nameserver 8.8.4.4

Save the new file and close gedit, then try the web. Is it ok?

That would appear to have resolved the issue.

Thanks :-)

Thanks

Hi, I'm running 64bit Ubuntu 20.04.3 LTS and recently lost access to my Ubuntu Software Center (maybe since I downloaded Steam?) But I've tried the fix above but my terminal does not accept "gksudo gedit /etc/resolv.conf"
Any other suggestions would be most welcome.

Just use sudo instead of gksudo

Sorry, that didn't work.

In Terminal I got the following -

sudo gedit /etc/resolv.conf
[sudo] password for dark:

(gedit:40757): Tepl-WARNING **: 10:48:12.276: GVfs metadata is not supported. Fallback to TeplMetadataManager. Either GVfs is not correctly installed or GVfs metadata are not supported on this platform. In the latter case, you should configure Tepl with --disable-gvfs-metadata.

and I can't make head nor tail of that although I didn't see this warning until I had changed the text to
nameserver 8.8.8.8
nameserver 8.8.4.4

Software Centre is still off-line to me....

If you run:

sudo apt update

Does it work OK?

It comes with a few issues with Launchpad:
Hit:1 http://gb.archive.ubuntu.com/ubuntu focal InRelease
Hit:2 http://ppa.launchpad.net/freetuxtv/freetuxtv/ubuntu focal InRelease
Get:3 http://gb.archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Ign:4 http://ppa.launchpad.net/lzh9102/qwinff/ubuntu focal InRelease
Hit:5 https://repo.steampowered.com/steam stable InRelease
Get:6 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]
Hit:7 http://ppa.launchpad.net/maarten-baert/simplescreenrecorder/ubuntu focal InRelease
Hit:8 http://ppa.launchpad.net/ubuntuhandbook1/avidemux/ubuntu focal InRelease
Err:9 http://ppa.launchpad.net/lzh9102/qwinff/ubuntu focal Release
  404 Not Found [IP: 91.189.95.85 80]
Get:10 http://gb.archive.ubuntu.com/ubuntu focal-updates/main i386 Packages [550 kB]
Get:11 http://gb.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages [1,294 kB]
Get:12 http://security.ubuntu.com/ubuntu focal-security/main i386 Packages [297 kB]
Get:13 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages [945 kB]
Get:14 http://security.ubuntu.com/ubuntu focal-security/main amd64 DEP-11 Metadata [29.0 kB]
Get:15 http://security.ubuntu.com/ubuntu focal-security/main amd64 c-n-f Metadata [8,844 B]
Get:16 http://security.ubuntu.com/ubuntu focal-security/universe amd64 Packages [646 kB]
Get:17 http://gb.archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata [283 kB]
Get:18 http://security.ubuntu.com/ubuntu focal-security/universe i386 Packages [512 kB]
Get:19 http://gb.archive.ubuntu.com/ubuntu focal-updates/main amd64 c-n-f Metadata [14.4 kB]
Get:20 http://gb.archive.ubuntu.com/ubuntu focal-updates/universe amd64 Packages [866 kB]
Get:21 http://security.ubuntu.com/ubuntu focal-security/universe amd64 DEP-11 Metadata [63.6 kB]
Get:22 http://security.ubuntu.com/ubuntu focal-security/universe amd64 c-n-f Metadata [12.7 kB]
Get:23 http://security.ubuntu.com/ubuntu focal-security/multiverse amd64 DEP-11 Metadata [2,464 B]
Get:24 http://gb.archive.ubuntu.com/ubuntu focal-updates/universe i386 Packages [642 kB]
Get:25 http://gb.archive.ubuntu.com/ubuntu focal-updates/universe amd64 DEP-11 Metadata [362 kB]
Get:26 http://gb.archive.ubuntu.com/ubuntu focal-updates/universe amd64 c-n-f Metadata [19.3 kB]
Get:27 http://gb.archive.ubuntu.com/ubuntu focal-updates/multiverse amd64 DEP-11 Metadata [940 B]
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/lzh9102/qwinff/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

Looks good, you should remove the PPA that doesn't support Focal. Does Software centre work OK now too?

Thanks, but forgive my ignorance about how I go about doing that (as a pensioner with limited techy skills)

What is the output of:

sudo grep -R qwinff /etc/apt/*

We can then remove the PPA and updates will be smooth

Thanks,

I got:

/etc/apt/sources.list.d/lzh9102-ubuntu-qwinff-focal.list.save:deb http://ppa.launchpad.net/lzh9102/qwinff/ubuntu focal main
/etc/apt/sources.list.d/lzh9102-ubuntu-qwinff-focal.list.save:# deb-src http://ppa.launchpad.net/lzh9102/qwinff/ubuntu focal main
/etc/apt/sources.list.d/lzh9102-ubuntu-qwinff-focal.list:deb http://ppa.launchpad.net/lzh9102/qwinff/ubuntu focal main
/etc/apt/sources.list.d/lzh9102-ubuntu-qwinff-focal.list:# deb-src http://ppa.launchpad.net/lzh9102/qwinff/ubuntu focal main

after entering the above

Hello,
Can someone please tell me which PPA.launchpad (listed above) to remove, in order to access Ubuntu Software Center and how to go about removing it?
Or should I launch a new question to find this out?

Any help would be greatly appreciated.

Just run:

sudo rm /etc/apt/sources.list.d/lzh9102-ubuntu-qwinff-focal.list.save
sudo rm /etc/apt/sources.list.d/lzh9102-ubuntu-qwinff-focal.list
sudo apt update

Should do it

Thank you for this fix.
I had to restart to finally access Software Center but it did work!
Thanks again