Can't paste text using CKEditor

I just installed CKEditor. When I tried to add a new product, I could not copy and paste text or link. For instance, I copy text somewhere, and I try to right click the mouse to paste text. It does not let me to do that. Even I try to click "Paste" on the panel, I still cannot get any resutls.

Please advice me what I should do. Thanks for your help.

I'm not sure what browser you are using but for IE10 the fix on this website worked for me.
http://dev.ckeditor.com/ticket/10450