100 % working method.Go to Dell official Website to download drivers . Search for "Dell Update for Windows Universal" download latest version.Install lastest version and when prompt for restart after installation is complete wait for 10 mins then restart your computer.After restart when booted to windows again wait for 5 mins for support assist to load all required services and then check for drivers and download in SupportAssist BOOM it will start working again.And your problem is solved .
I have an out of warranty G3 15 3500 with windows 10 21H2. SupportAssist get drivers updates tab showing an error : " System is busy, please try again later" every time I check for update. I have tried uninstalling and reinstalling SupportAssist but it didn't solved the issue. I am in windows 10 21H2 with all drivers at latest version and SupportAssist also on version 13.3.5.0.
G3 15 3500, SupportAssist "Get drivers updates" show an error message