[Koha] Can't check out books

i can't find any books that i can check out. I can only put in the basket, but I couldn't check out and i figure that, it must be related to the issues. can anyone help? thanks _________________________________________________________________ Express yourself instantly with MSN Messenger! Download today - it's FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/