Please perform a clean uninstall of SA (SupportAssist) by following steps below: Solutions for Common SupportAssist Installation Issues Support Assist for PCs and Tablets Clean Uninstall and Reinstall     
Dell Inspiron 15 3567, 64-Bit OS Windows 10 Pro version 1909 supportassist will not install have updated all bios and done everything listed on this board but nothing works.When I go to install supportassist it tells me from my 3rd party software a new startup item has been added but supportassist tells me "installation Canceled" and never does install. I had to replace the original HDD with a new HDD that is the only difference from original configuration as I am at wits end on this conflict for I have spent hours trying to resolve this issue does anyone out here have a fix for this problem?  Thanks Tc
Inspiron 15 3567, Windows 10 1909, SA won't install