"Skype" is a communication program that allows you to video-chat with friends, send instant messages and organise your contacts. You can also use "Skype" to customise your contact list for people you do and don't want to chat with. If you've had a falling out with a friend or simply haven't talked for a long time, you may have been blocked by a particular "Skype" contact. While there's no definite sign that you've been blocked, a few clues can let you know that your status has changed with a friend.
Launch "Skype" and sign in with your username and password. When your contact list loads, check the icon beside a contact's name. If a person has blocked you, the icon may turn from the grey "x" icon or green check mark to a grey question mark. This means the person isn't sharing his information with you, which is a sign of being deleted or blocked.
Click the person's name to open a new chat window and send an instant message. Since a person who has blocked you will no longer be able to see any communication from you, the message will either be returned as undeliverable or may simply be shown as processing indefinitely. This likely means you've been blocked.
Check the person's profile picture. If you've been blocked, you'll no longer see a personalised profile picture, but the stock "Skype" avatar. This means the contact has stopped sharing personal information with you.
Add your findings to less-measurable signs that you might be blocked, such as a sudden change in your frequency of communication with a certain person, a recent argument or fallout or simply not hearing from the friend for a long time. When combined with some of the more concrete signs, you can decide whether or not a contact has blocked you.
Make sure to be nice so you won't have to worry about someone blocking you ;)