Your most important piece of software is an Excel file

In a lot of companies there is one file that matters more than any piece of software they ever bought. It is called something like Prices_2026_final_v3.xlsx, it sits on a network drive, and out of it come the quoted prices, the volume tiers for the three largest customers and the surcharge for rush orders. If that file breaks, sales stops. If it ends up in the wrong hands, someone knows your margin.

That file is about to get a little more capable, and that is a good reason to think about it for once.

What is changing in Excel right now

Microsoft is rebuilding Excel so that a single cell can hold lists and nested arrays, Golem reports. A cell is then no longer one value, it can contain a small table of its own. For everything that is solved today with helper columns, concatenated text and six sheets in the background, that is real relief.

The English-language trade press is less enthusiastic. The Register sums up the same change under a headline saying that Microsoft is now cramming multiple values into Excel boxes. The objection behind it is practical, not ideological. A spreadsheet is popular because you can check with your own eyes what is in it. As soon as a cell contains a whole record, that visual check is gone, and you only notice a mistake in the result.

The bottom line is that your most important file can do more and will therefore live longer. That is not a problem. The problem is three points at which a spreadsheet stops carrying the load, no matter how many features it has.

When two people write into it at the same time

The first point is reached when two people need the same row. On a network drive that ends with a copy called ..._copy_Meier.xlsx, in the cloud version with simultaneous editing where the last one wins and nobody notices what was overwritten.

The criterion is not the number of users, it is simultaneity. If three people read the file and one person maintains it, that holds for a long time. If two schedulers enter appointments at the same time on a Tuesday morning, it does not hold, and no feature in the spreadsheet changes that.

When nobody knows where a number came from

The second point is reached when somebody asks why the customer got 4.80 in March and 5.10 in July, and nobody can answer. The formula shows today's result. Who changed which value when, and for what reason, is written down nowhere.

This is the expensive one, because it only shows up during a complaint or an audit. If a system puts out a number and nobody can trace where it came from, the number is worthless. There is a test for it that takes two minutes. Take the last price change and try to find out who entered it and why.

When only one person still understands the formulas

The third point is the one everybody knows and nobody likes to say out loud. The file has grown over years, and exactly one person knows why there is an IFERROR in column M on sheet 4. If that person is out sick, resigns or retires, what is left is a file that keeps calculating and that nobody can change any more.

There is a test for this one too. Ask someone else on the team to enter a volume tier for a new customer. If that person has to ask the one person to do it, you know where you stand.

Four paths, and the convenient one is rarely the right one

If one of the three points is reached, you have four options, not two.

• Tidy up and stay in the spreadsheet. Separate input from calculation, protect the cells with formulas, name your ranges, add a sheet with a plain change log, back it up daily. That costs two to three days and often buys you two years. Sensible as long as only one person writes.
• Rent finished software. Paid per head and month, runs at the vendor, available quickly. The price is that your process adapts to the software and your data sits somewhere else.
• Someone else's software on your own server, maintained by someone else. Between doing it yourself and renting lies this third category, and it is the one most often overlooked. You take an existing, open solution, it runs on a server that belongs to you, and updates, backups and incidents are handled by a service provider. This is the category we work in, and we run what we set up.
• Your own application for the core. Not for everything, just for the one thing that makes your business what it is. The pricing, the scheduling, the quoting logic. Everything else stays where it is.

The fourth path does not have to mean that Excel disappears. Often the best solution is for the application to hold the rules and the history while the spreadsheet stays input and output, because your sales team knows how to work with it. An export that looks exactly like the old file saves you half the arguments about rollout.

Where a machine helps and where a person decides

When you move out of a spreadsheet that has grown over years, there comes a point where 4,000 articles with inconsistent names have to be mapped. That is work a machine can prepare well. It proposes mappings, flags the cases it is unsure about and puts those in front of you separately.

A person signs off, and it is the person who is responsible for the prices. Not as a formality, but because the uncertain cases almost always need knowledge that is written down nowhere in the file. A machine that makes a proposal takes nobody's job away. It takes away the two weeks that would otherwise have gone into retyping.

How you decide

Before you talk about software, settle on two numbers. How long may this file be unavailable before the business stops. And how much work may be lost if it breaks, an hour or a day.

If the answer to the first question is „two hours" and the file sits on a network drive with no history, you do not have an Excel problem. You have an open bill, and the new features in the spreadsheet only move the date on which it falls due.