If you have a legitimate license, the update is simple. If you are using a common clone interface (Yellow Full Chip version), follow this community-vetted process:
Diagbox 7.58 brings several improvements, including: diagbox 7.57 to 7.58 download
Updating DiagBox is not like updating Windows software. It is sensitive to driver conflicts, antivirus interference, and incorrect patch orders. If you have a legitimate license, the update is simple