Your old computer might not be compatible or there is an error. Support Assist is not a necessary app and has to be the right version for each model computer. It's really for new computers with brand new users. Sign up for notices of (rare) updates at the bottom of this page--Support for Latitude 5500 | Drivers & Downloads | Dell US You might be able to download Support Assist on that page if you allow Dell to scan your computer.
Dell Latitude 5500, trying to run SupportAssist, fails immediately saying: Download failed: "We were unable to download a file for installation. Check your internet connection and try again."   I check the log in C:\ProgramData\SupportAssist\Client\Agent\logs\ApplicationLogs ->  ERROR Dell.Services.SupportAssist.SecurityUtility.CertificateUtility - Failed to validate the url certificate   Anybody can help? Gr, David
Cannot install SupportAssist -> URL Validation failed