Why does Skype suddenly fail to log in? Turns out, it's tor!

Update: Turns out this answer is wrong. The problem here was Skype blocking IPs operating a Tor exit node. See answer below.

However the answer might be helpful in solving other problems.

Here is what I did.

All this was done using terminal. Just press Ctrl+Alt+T on your keyboard to open Terminal.

I removed the old Skype, using sudo apt-get autoremove --purge skype, and removed ~/.Skype folder.

I then installed Skype 4.2.0.11 this way.

wget -O skype-NoobsLab.deb http://download.skype.com/linux/skype-ubuntu-lucid_4.2.0.11-1_i386.deb
sudo dpkg -i skype-NoobsLab.deb
sudo apt-get -f install;rm skype-NoobsLab.deb

After the installation was done, I typed Skype in Dash, clicked on it, and when it opened, I put in my user name and password, and was able to log in. See below.

Note: I used the 32bit Skype, and there were no problems.

This method will automatically detect OS architecture and install latest skype:

sudo add-apt-repository "deb http://archive.canonical.com/ $(lsb_release -sc) partner"
sudo apt-get update
sudo apt-get install skype && sudo apt-get -f install

Note: I had to install libqt4-webkit, and for that I used Synaptic.

^{Source: Noobslab}

The recent consensus is that Skype doesn't work well with tor and similar programs. That's what's causing the problems. Skype has automatically blocked a few massive amount of IPs running tor exit nodes. If you are experiencing the problem so far there are only two practical ways around it:

1. Disable tor (both node and client usage!). After a day or two Skype should start working again. Should the problem persist enable logging:

   mkdir ~/.Skype/Logs
   cd ~/.Skype/
   mv shared.xml old_shared.xml
   sed 's/<Lib>/<Lib>\n    <LogLevel>3</LogLevel>/g' old_shared.xml > shared.xml
   

   Then restart Skype, wait for the error to occur. After it post your logs in ~/.Skype/Logs in the appropriate thread of the Skype forum. They will help you! They will not react.

2. Configure a proxy for use with Skype:

   1. Click the Skype-Icon and select Options

   2. Under Advanced, put your proxies details for Host, Port and optionally User and Password in the appropriate fields. If you don't know a good proxy already, you need to find a trustworthy list via google. I found hidemyass to be useful. Security is more important than speed!

   3. Make sure ports are forwarded to your PC (for your proxy and incoming) connections).

3. Use a VPN connection (e.g. company or university network)

Update:

Skype support does not react to inquiries into this problem anymore. I find that very disturbing. There are multiple closed threads - all labeled offtopic. Either tor is unwanted because it gets in the way of data mining or tor users are indiscriminately blocked because of the spam emanating out of the network into Skype. Both explanations are ultimately evil.

Did you try to fix the packages ?

sudo apt-get update && sudo apt-get install -f && sudo apt-get update && sudo apt-get upgrade -y

I try this solution, and it didn't work for my ubuntu 14.04(x64).

at finally, I remove all skype package and reinstall can resolve it.

new version is (4.3.0.37)

remove:

1. sudo apt-get autoremove --purge skype

2. sudo apt-get autoremove --purge skype-bin (optional)

3. sudo apt-get autoremove --purge skype:i386 (optional)

install:

sudo apt-get install skype

To me it seems the problem of version 4.2 !! I uninstalled it from the terminal, downloaded 4.3 (.deb for ubuntu 12.04) from the Skype website and installed using the software centre and it worked fine. Using Microsoft is always a pain in the a** (even though it was working fine on my MacBook).