Hi can you try to log on at skype.com website to test your account details , update as needed.
if you still have issues once you have adjusted your account , made sure of access .
On your Mac under Look in Mac HD / Library / Preferences/ find the com.skype.skype.plist . Move the file to the trash then restart the Skype app. Let me know if that works , You can reinstall the Skype app if you have any doubt it is ok .
Only download Skype from their own website http://www.skype.com/intl/en-gb/home
Does this help , thanks.
Sorry but I do not wish to accept. Your answer would not have helped me. I discovered the reason for the problem on my own while I was waiting for an answer. It was simple, but in fine print. The screen kept asking for my account name and password XXXXX only in very fine print did it essentially say, click here to establish an account name. If I would have gone to skype.com to test account details. The result would have been the same - we don't recognize you. Gary Fischer
ok glad you got it fixed , your where just setting up your account then .
You can setup an account more easy on the website if there are problems , Thanks.