The number one cause of "Request Download URL Failed" is a DNS (Domain Name System) failure. Your ISP’s DNS may be blocking or misdirecting Droid4X’s request. Switching to a public DNS like Google or Cloudflare solves this instantly.
Before applying fixes, perform basic diagnostics: how to fix droid4x request download url failed work
C:\ProgramData\Droid4X\Logs\
C:\Users\<username>\AppData\Local\Droid4X\
Search for "url", "failed", "timeout".Before deep fixes, try these: