CustomError
TURN DEAD LINKS, 404s AND OTHER SITE ERRORS INTO GOOD TRAFFIC (& SET UP IIS ERROR PAGES EASILY). A ? page cannot be found' message on your site might as well be ? STOP? to your users. To get them back on track, CustomError for Microsoft IIS allows developers to add their own error pages (or... Take advantage of wasted traffic by redirecting your dead links to new content and saving your SEO ranking work with CustomError. ... 0, IS AVAILABLE AS A FREE, FULLY FUNCTIONAL 30-DAY TRIAL, and as with all Port80 IIS tools, is very affordable and includes free technical support.
http://www.customerror.com/download/cesetup.exe - 1Mb - Download - Screenshot