Bloodhound.Exploit.289 keeps coming back?

My company currently uses Symantec Endpoint Protection Client, and it is reporting that we have 119 (and climbing) quarantined cases of Bloodhound.Exploit.289 on one machine. In addition, there are 12 listed under "Newly Infected" and 18 under "Still Infected"--all on the same computer. We have had this problem at least twice before on this machine, despite the fact that we follow the removal guidelines on the Symantec site each time. Does anyone know why this could be happening or have any suggestions? Thanks in advance!