How to install an extension in Business Central and test it first

What an extension is and the kinds you will meet

An extension is a package of AL code that adds to Business Central. It leaves Microsoft's base application alone. It can add fields, pages, reports, tables and logic. Because it sits beside the standard code, Microsoft can update the platform underneath. The extension keeps working as long as its publisher keeps it current.

You will meet three kinds. Microsoft ships some with the product, such as the Shopify connector. Independent publishers sell marketplace apps. A developer writes a per-tenant extension for one customer and hands it over as an app file. The Extension Management page lists all three together.

How to install an extension in Business Central from the marketplace

Search for Extension Marketplace, or choose the matching action on the Extension Management page. Find the app and choose Get it now. Accept the publisher's terms if you agree with them. You return to Business Central. Pick the language and choose Install.

The install runs in the background. Open Deployment Status from Extension Management to watch progress and read any error. When it finishes, users sign out and in again, or refresh the browser. Then the new pages and fields appear. Many apps need their own setup and a separate subscription from the publisher.

Install an extension in Business Central from an app file

For an extension built for your company, the developer sends a file that ends in .app. On Extension Management, choose Upload Extension and select the file. Then decide when it should deploy. You can deploy it now, or hold it for the next minor or major update. Accept the notice and choose Deploy.

Upload files only from a developer you trust, and keep a copy of the source code. A per-tenant extension runs with access to your data. You will need the source when you change it or prepare it for a later release. We advise keeping it in a repository your company controls.

Test in a sandbox before production

Create a sandbox as a copy of production from the Business Central admin center. Install the extension there. Run the processes it touches from start to finish with real examples, such as an order, a posting and a report. Look for changed page layouts, new mandatory fields and slower pages, as well as the feature you wanted.

Check permissions too, because a sound install of an extension in Business Central also covers who may use it. Most extensions bring their own permission sets. Users cannot see the new functions until you assign them. When the sandbox run looks clean, repeat the same install in production at a quiet time. Tell users what will look different.

Updating, uninstalling and looking after extensions

Publishers update their marketplace apps. You can apply those updates from the Apps list of the environment in the admin center. A per-tenant extension is your job. Before each release wave, compile the code and test it against the preview version. That way the update does not stall.

To remove an extension, choose Uninstall on Extension Management. Business Central keeps its data by default, so a reinstall brings everything back. Deleting the data is a separate, deliberate choice. This is the last step in managing an extension in Business Central over time. If an app will not install, or you have extensions nobody remembers ordering, our consultants can go through the list with you.

Business Central extension install: FAQ

Who can install an extension in Business Central?

A user needs permissions for extension management. Administrators normally hold them through the relevant permission set. Ordinary users cannot install apps. Keep this right with a small group so nothing goes in without a test. Also record who holds the right, so you know whom to ask when an app misbehaves. A short list makes audits and handovers simple.

Does an extension apply to one company or to all of them?

An extension installs for the whole environment, so every company in it gets the new objects. Whether the feature runs in a given company usually depends on the app's own setup page. You complete that page for each company.

Will an extension break when Business Central updates?

Well-kept extensions keep working, because publishers test against each release wave. A per-tenant extension that relies on something Microsoft removed can block an update until someone fixes it. So test against the preview version in a sandbox. Do this before each release wave, and keep the results with your change notes. Then you can show what you checked if anyone asks later.

What is the difference between uninstall and unpublish?

Uninstall switches the extension off for the environment but leaves it ready to install again. Unpublish removes the package itself. It applies to per-tenant extensions you uploaded. In both cases the data stays unless you choose to delete it.

Is it better to buy an app or have an extension built?

If a marketplace app covers the need and its publisher keeps it up, that is usually the lower-effort route. The publisher handles updates. A custom extension suits needs that are specific to your business. We compare both honestly before we advise one. First we list what the app does today. Then we list what you need, and the gap decides the answer.

Related extension and development pages

This guide showed how to install and manage an extension in Business Central. These pages cover our extension and marketplace services, the admin center and the sandbox environments you test in. Use them when you need help choosing apps or getting an extension written. Our consultants can also plan the sandbox test with you, so that your first install goes smoothly. Start with the admin center page, since it explains the environments that every install touches. For the product detail, see Microsoft's guide to installing and uninstalling extensions.