Internet connection is working.

apt-get is working.

Trying to add ppa:cooperjona/lightread but an error has raised:

Cannot add PPA 'ppa:cooperjona/lightread' . Please check that the PPA name or format is correct.

I supposed there is an error in writing or in the PPA.

I tried also the 'ppa:tombeckmann/ppa' but with same error.

  • The issue comes from your system, not the PPA, which works fine for me. – MrVaykadji Mar 5 '14 at 12:01
  • I tried all of this here and still got the same error. – user2117580 Jun 19 '14 at 20:21
  • If anyone of you ends up here and is using a proxy, check this thread instead – eis Nov 17 '15 at 11:27
  • @Anwar: I don't understand how the two are related. The accepted answer here is about certificates and not web proxy servers. – David Foerster May 18 '17 at 22:16
  • @DavidFoerster The linked answer has addressed both the issue and I feel that it's same problem with different answers. – Anwar May 19 '17 at 5:03

Open Terminal and run the command

sudo apt-get install --reinstall ca-certificates

It may work, but if doesn't then run

sudo -E add-apt-repository ppa:ppaname/ppa

instead of sudo add-apt-repository ppa:ppaname/ppa

  • 6
    note to reader: sudo -E preserves the user environment, including any proxy config. – eis Apr 29 '16 at 12:04
  • Or if you're on a https restricted network and have to install another root certificate to trust the networks MITM policy, here's something that will help: askubuntu.com/questions/645818/… – Tim Lewis Dec 14 '17 at 2:16

I googled the error and find this. So i tried to clone a git as he did there and has the same result.

So to solve this:

sudo apt-get install --reinstall ca-certificates

and things become smooth again :)

  • 6
    I tried this, but the same error exist and it does not work, ain't it odd? – Mohammad Rafiee Dec 6 '14 at 5:20

I had this exact error message about checking the PPA name or format. My network was connected and I could ping websites and browse fine.

What I finally figured out was the clock on my computer was set wrong. If it's off more than a small amount, the secure connection will fail and it will report this message. It's very unhelpful.

Check your clock. I set mine and then it immediately worked as expected.

  • Another issue causing this issue is a firewall (like Shorewall) blocking access to the internet. I had the exact same message - there was no other indication that the firewall was blocking.Though it worked after opening a port. – Carsten Schmitz Jun 13 '18 at 10:54

protected by Maythux Nov 17 '15 at 12:49

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