Reverse-Engineering a 40-Year-Old Copy Protection Dongle for Legacy Accounting Software
By
zdw
Master baker tier. Every paragraph earns its place on the tray.
Summary
The article details the author's experience reverse-engineering a 40-year-old copy protection dongle to run legacy accounting software. The software was built using RPG (Report Program Generator), an older programming language than COBOL, and was used with IBM's midrange computers. The author helped a friend's accounting firm migrate away from this decades-old system, which required defeating the hardware-based copy protection mechanism that had prevented the software from running without the original dongle.
Key quotes
· 3 pulledThat's right — this little device is what stood between me and the ability to run an even older piece of software that I recently unearthed during an expedition of software archaeology.
For a bit more background, I was recently involved in helping a friend's accounting firm to move away from using an extremely legacy software package that they had locked themselves into using for the last four decades.
This software was built using a programming language called RPG ('Report Program Generator'), which is older than COBOL (!), and was used with IBM's midrange computers such as the Sys
Article URL: https://dmitrybrant.com/2026/02/01/defeating-a-40-year-old-copy-protection-dongle
Comments URL: https://news.ycombinator.com/item?id=46849567
Points: 5
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