Guide for companies
Modernising outdated business software
Updated August 2026
Almost every company has a piece of software that “works, but”: it runs on a PC nobody dares switch off, one person alone knows it, and every change request gets the same answer — “can’t be done”. That is not an IT problem: it is an operational risk with an invisible monthly cost. This guide covers how to recognise the moment to act, what postponing costs, and the three viable paths.
The signs it is time to act
No software should be rebuilt because it is old: it should be rebuilt when its age starts to cost money. These are the symptoms that matter.
- It depends on a single person (internal or external): if they are gone tomorrow, nobody can touch it.
- It only runs on one specific machine that nobody can update or switch off.
- The original supplier no longer exists, or answers at hostage-taker rates and timelines.
- The data lives inside and cannot be extracted: every report is manual work.
- It does not talk to the other systems: the same data is retyped two or three times.
- People work around it: parallel spreadsheets, double entries, handwritten reminders.
- It cannot be used outside the office, and work now happens outside the office too.
What NOT modernising costs
Old software feels free because it is already paid for. In reality it bills you every month, in forms that appear on no invoice.
Lost hours
Retyping data, working around limits, waiting for the slow machine: half an hour a day for five people is 25 hours a month. At full company cost, thousands of euros a year — every year.
Downtime risk
Software living on a single machine, without sources and without a supplier, is a production stop waiting to happen. The question is not if, but when — and what that day will cost.
Decisions in the dark
If extracting a figure is a project, figures do not get looked at. You decide by feel where competitors decide on numbers.
Frustrated people
Younger employees will not accept working like it is 2005. Obsolete tools are a cost at hiring time too.
The three possible paths
Not everything needs rebuilding from scratch — quite the opposite: total rebuilds are often the wrong call. The real options are three, in order of invasiveness.
1. Secure it
The software stays as it is, but stops being a bomb: sources are recovered, documentation written, the system moved to a modern or virtualised server, backups automated. Typical cost: a few thousand euros.
When it fits: When the software still does its job well and fragility is the only problem.
2. Extend it
The old system remains the core, and what is missing gets built around it: a modern web interface, an app for people off-site, a data bridge to other systems, a reporting dashboard. Typical cost: €10–40,000.
When it fits: When the underlying logic is still valid but access, integration or reporting are not. The right path more often than people think.
3. Replace it
Rebuild, either bespoke or by adopting a market product to customise. The most expensive and longest path, and the classic mistake is rebuilding as a photocopy of the old instead of rethinking the process. Typical cost: €30,000 and up.
When it fits: When the logic itself no longer matches how the company works, or the technology prevents any extension.
The mistakes that cost the most
- Postponing until it breaks: emergency work costs three times as much and happens under the worst conditions.
- Rebuilding everything at once: the monster project that sets out to replace everything and 18 months later has replaced nothing.
- Photocopying the existing system: reproducing the old software’s flaws in the new one “because that is what we are used to”.
- Not demanding sources and code ownership in the new contract: in ten years the same problem returns, identical.
- Leaving data migration to the end: cleaning and migrating historical data must be planned from day one — it is often half the work.
Frequently asked questions
My ERP is 15 years old: does it have to be rebuilt?
No. Age alone is not a reason: if it does its job well, securing it (sources, backups, a modern server) or extending it is often enough. Replace it when its logic no longer matches how the company works.
How much does modernising business software cost?
It depends on the path: securing costs a few thousand euros; extending with interfaces, apps or integrations €10,000–40,000; replacing from €30,000 up. A good developer always starts from an analysis of what to keep, not from a total-rebuild quote.
We no longer have the source code: are we stuck?
No, but it must be addressed now. The options: recover it from the original supplier (often a negotiation), work around the software by connecting to its data, or plan the replacement calmly while everything still works.
Bespoke software or a market product?
If your processes are standard, a customised market product costs less. If your way of working is your competitive edge, bespoke avoids bending the company to the software. Very often the right answer is a hybrid.
Who can do this kind of work?
You need a developer used to working on existing systems — recovering data, integrating, extending — more than building from scratch. On Araknet you can describe the situation anonymously and receive proposals from freelance developers who have handled similar systems, with approach and quote.
See also: Bespoke management software: the complete guide · What software development costs.
Describe your software, even if it is a mess
Post the situation anonymously on Araknet: nobody will know it is your company. Receive concrete proposals from freelance developers who have seen plenty of old systems — with approach, price and timeline.
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