Hi, everyone. I had the same problem. Today I use "Alienware Update"(You can find this app in your start menu.). There is an update for SupportAssist. Now my version of SupportAssist is 3.1.4.49.  I just check  "Get Drivers and Downloads". Now everything looks fine.It works normally and shows me "none available". I am not sure this is the reason or not. Just want to share this with everyone.
Initially I was not able to update my drivers or scan my hardware, so I uninstalled SupportAssist, deleted all the folders, and redownloaded it. I was able to successfully scan my hardware, but I still am unable to see if there are any drivers I should download.   When I click "run now", it will run for a few seconds, and then say that there was an "unexpected error" in red.    Any suggestions on how to fix this would be much appreciated. Thanks!
SupportAssist 3.4.0 "Get Drivers and Downloads" not working