Mine started freezing on launch. Went to C:\Program Files\Dell\SupportAssistAgent\bin\Resources\New-Dell-Logo-White-Small.png and deleted -Small. Should look like New-Dell-Logo-White.png.  Working now.      
Tried using SupportAssist a second time, error message states the obvious: SupportAssistUI freezes. Attempted to download S.A. for a reinstalled, but disallowed saying latest version already installed.  
New Inspirion; SupportAssist UI freezes, worked once before.