My b2evolution Version: 1.10.x

Since my skin doesn't work, my blog doesn't work. HELP.

I downloaded a skin. Unzip it. Upload it. Chose it. And...

this is the error message:

The default skin [niftyyellow] set for blog [KKF Blogger] does not exist. It must be properly set in the blog properties or properly overriden in a stub file. Contact the webmaster...

Now I can't even login to my blog to change the skin.

hi i'm new in here...Please send me a link on how to solve this problem.