This tag is far too tenacious. The links seen on thing page point to its recurring attack, and it is just too general. However, I fear that blacklisting it could open tags like error-handling up to misuse for general errors, not specifically error handlers. In fact, it already is being a little mishandled(no bad pun intended) in this way.
We don't generally blacklist tags just because they shouldn't exist. It's only if they're being pervasively and wrongly used that blacklisting is considered. There were only two questions tagged error. I retagged them. While I agree this is a terrible tag, I don't see how it's worth blacklisting.