I just discovered this problem this morning when upgrading. I cannot log into Skype. When I type something in the box, it doesn't show up. It was all working before(I use Skype 6.5). I searched, but all of the solutions did not work, or at least what I can find. I use Windows XP, by the way.
Make sure you have Service Pack 3 and Internet Explorer 8 installed.
Please do a Skype reset.
Type: %appdata% and press Enter.
Rename the folder "Skype" to "Old_Skype"
Go to the, C:\Documents and Settings\All Users\Application Data\Skype\Apps
Rename the folder login to login1.