your post isn't clearly written. You mentioned fibers, but you say you activated them. Did you mean you haven't?

You haven't really given enough information about what is or is not working. Something tried to run, but SQL Server Agent wasn't running, or was stuck starting. Can you provide more details about what is wrong, or what else appeared in the log?

Also, please don't use the subject line as part of your post. Please write all information so we can easily follow what happened.