Adobe's website probably doesn't host old versions anymore, especially for products as outdated as Distiller 4.x/5.x. Those were from the early 2000s. Pagemaker 7.0 was even earlier, from 1998. So compatibility is a big issue here.
The user might be trying to use legacy software for a specific task, maybe restoring an old document. They might not be aware that Adobe has discontinued support for these products. I should inform them about the risks of using outdated software, like security vulnerabilities and lack of support. Adobe's website probably doesn't host old versions anymore,
I should structure the answer by first confirming the unavailability, then alternatives, and then options if they still insist on using the old versions. Make sure to highlight security concerns and suggest contacting Adobe support as a last resort. So compatibility is a big issue here