Bill you could try to get rid of it in safe mode. Another thought might be that it's not the "Download Accelerator Plus" that is causing the problem but whatever it is that you are downloading with it maybe? I have no idea what that is but it's a possibility. There are also other protections that you can use in addition to Spybot.

safe mode directions
http://service1.symantec.com/SUPPORT/tsgeninfo.nsf/docid/1999101916343139