HTTP redirect not working

Yep, that worked. Try this:

when HTTP_REQUEST {
    set myuri [string tolower [HTTP::uri]]
    switch -glob $myuri {
        */livelink/livelink.exe* {
            set replaceURI [string map [list /livelink/livelink.exe /OTCS/cs.exe] $myuri ]
            set cachecontrol {no-cache}
            set pragma {no-cache}
            set location "http://ContentServerQA.idexxi.com$replaceURI"
            HTTP::respond 301 noserver "Location" $location "Cache-Control" $cachecontrol "Pragma" $pragma "Connection" "close"
        }      
    }
}