Apache errors/need help fixing

I’ve been trying to block some bad IP addresses and put them in my .htaccess with the deny rule and now in the Apache error log I am getting these types of errors.

[error] [client] client denied by server configuration

At first I thought it was a good things because it’s being blocked but it’s coming up as an error. Can anyone explain why?

This address happens to be a spider too.

It’s an “error” inasmuch as the user (or spider, or whatever) that made a request to your web site got an error, rather than a normal response. This is the expected result.