Business Central 2026 release wave 1 (BC28): Storing Document Attachments outside the database (No customization) – See benefits of external storage support for document attachments

Hi, Readers.
Dynamics 365 Business Central 2026 wave 1 (BC28) is generally available. More details: General Available: Dynamics 365 Business Central 2026 release wave 1 (BC28)

I will continue to test and share some new features that I hope will be helpful. In this post, I would like to talk about See benefits of external storage support for document attachments.

See benefits of external storage support for document attachments:

Business value:
This feature helps you manage document attachments more efficiently by storing them in external systems such as SharePoint or Azure storage instead of the Business Central database. By offloading large or frequently used files, organizations can keep their environments performant, reduce storage growth, and better control costs without changing how users work with documents. You get improved scalability and flexibility, especially in document‑heavy processes like invoicing, purchasing, and project management. Documents are fully accessible from Business Central, while IT teams gain more control over storage and retention using familiar external platforms.

https://learn.microsoft.com/en-us/dynamics365/release-plan/2026wave1/smb/dynamics365-business-central/external-storage-support-document-attachments?wt.mc_id=DX-MVP-5004336

On most list pages, cards, and documents, you can attach files on the Attachments tab of the FactBox pane. You can attach any type of file, such as text, image, or video files, to a card, document, or a line on a document. This is very useful.

The attachments that users add to BC will increase the database capacity. This is a matter of course. Attachments are saved in the database using the Media data type.

PS: Using the Media or MediaSet data type provides better performance than using a BLOB data type and is more flexible in its design. With a BLOB data type, each time the media is rendered in the client, it’s retrieved from the SQL database server, which requires extra bandwidth and affects performance. With the Media and MediaSet data types, the client uses media ID to cache the media data, which in turn improves the response time for rendering the media in the user interface. More details: Working With Media on Records

But the capacity of BC is not infinite. By default, Business Central customers can use up to 80 GB of database storage capacity across all their environments (production and sandbox). This limit means that the sum of database capacity usage across all of their environments must not exceed 80 GB.

Apart from the default storage capacity, the customer is entitled to additional storage capacity based on the number of Business Central licenses they own:

More details: Announcing: Dynamics 365 Business Central database capacity changes as of July 1, 2021 and Managing capacity

PS: Dynamics 365 Business Central: What happens when the capacity limit is exceeded (Exceeding capacity quota)

So some customers will consider saving attachments externally. In Manage attachments in SharePoint (Save attachments externally and do not use BC capacity), we discussed how to manage attachments in SharePoint through customization.

Microsoft recently announced that this is now possible with standard features, more details: What’s Cooking in Business Central: Storing Document Attachments outside the database

This feature was initially introduced in BC27.x, but my initial tests with SharePoint connections were unsuccessful. It was later discovered that the issue was likely caused by an expired Microsoft 365 license in my test tenant.
I’ve retested it in BC28.0 and can confirm it now works perfectly. Furthermore, Microsoft has officially included this enhancement in their 2026 Release Wave 1 plan, See benefits of external storage support for document attachments

So in this post, I’d like to briefly introduce and share this new feature. Let’s see more details.

Here is a new settings page, Set Up External File Accounts. More details: Set up an external file storage account

This can also be found in Assisted Setup.
Connect to external file accounts: Configure external file accounts to be used in app scenarios, for export of data out of Business Central.

Choose Next.

Currently, four Account Types are supported. The settings are different for each Account Type.

In this test, I will use SharePoint just like my customization. Choose Next.

Therefore, we need to make some preparations in advance.

Registering your application establishes a trust relationship between your app and the Microsoft identity platform. This part of the setup is the same as in Using OAuth to connect Business Central APIs and Web Service in Postman. Just the API permissions are different.

To configure application permissions for the app in the app registrations experience on the Microsoft Entra admin center, follow these steps:

• On the application’s API permissions page, choose Add a permission.
• Select Microsoft Graph > select Application permissions.
• In the Select Permissions dialog, choose the permissions to configure to the app.

This time I only added Microsoft Graph -> Application -> Files.ReadWrite.All.

PS:
1. Upload or replace the contents of a driveItem permission

2. You can also directly set SharePoint API permissions.

At this point, we will get the following three settings.

Tenant Id: f276c3d9-df86-426c-b125-20610aa4380a
Client Id: cdf400b8-5ef7-426c-9f6b-a91d84160b92
Client Secret: QXc8Q~jCvCz6xegzqPneSwdaA0-w-v_S-xxxxxxx

This covers most of the essential setup requirements.

PS: This is similar to the settings in Postman.

There’s one more important step: Add https://businesscentral.dynamics.com/OAuthLanding.htm in Manage -> Authentication -> Redirect URI configuration.

There are two additional SharePoint settings that need to be configured.

SharePoint Name: https://yzhubc.sharepoint.com/sites/yzhubc

Base Relative Folder Path: Shared Documents/BC

Sign in to your account

yzhubc.sharepoint.com

All configurations have been successfully completed. Choose Next.

Done.

Then we can go to the External File Accounts page to verify the settings and proceed with the next steps.

You can choose Home -> Storage Browser to confirm that the recent setups have taken effect in the system.

Choose Allow Always.

If you can open the External Storage Browser page, then the settings are correct.

You can upload a test file to the SharePoint folder. If you can see it in BC, then everything is OK.

Additionally, after changing the External File Accounts page to List, you can click on Name to change the settings you just made.

PS: You may encounter the following problems

1. Check API permissions in App registration

Sorry, but we’re having trouble signing you in.

AADSTS650057: Invalid resource. The client has requested access to a resource which is not listed in the requested permissions in the client’s application registration. Client app ID: cdf400b8-5ef7-426c-9f6b-a91d84160b92(BCDemo). Resource value from request: 00000003-0000-0ff1-ce00-000000000000. Resource app ID: 00000003-0000-0ff1-ce00-000000000000. List of valid resources from app registration: 00000003-0000-0000-c000-000000000000.

2. Please check if a Redirect URI is set.

Sorry, but we’re having trouble signing you in.

AADSTS500113: No reply address is registered for the application.

3. Please check if the correct Redirect URI has been added, https://businesscentral.dynamics.com/OAuthLanding.htm

Sorry, but we’re having trouble signing you in.

AADSTS50011: The redirect URI ‘https://businesscentral.dynamics.com/OAuthLanding.htm’ specified in the request does not match the redirect URIs configured for the application ‘B4FE1687-F1AB-4BFA-B494-0E2236ED50BD’. Make sure the redirect URI sent in the request matches one added to your application in the Azure portal. Navigate to https://aka.ms/redirectUriMismatchError to learn more about how to fix this.

4. Please check if your Microsoft 365 (SharePoint) license is valid.

If requesting support, please provide the following details to help troubleshooting:

Error message: 
An error occured.


Internal session ID: 
99c47ce1-c24b-492d-a82f-d303379fca3d

Application Insights session ID: 
dc77b6fd-ffc0-4b51-a79d-216a1675d299

Client activity id: 
a2d5aa3f-96e0-443e-b9fb-faaadb65a0ad

Time stamp on error: 
2026-04-13T06:26:33.5726007Z

User telemetry id: 
ca6d165a-5913-41b0-b928-5b85a1ce519b

AL call stack: 
"Ext. SharePoint Connector Impl"(CodeUnit 4580).ShowError line 4 - External File Storage - SharePoint Connector by Microsoft version 28.0.46665.48257
"Ext. SharePoint Connector Impl"(CodeUnit 4580).ListDirectories line 10 - External File Storage - SharePoint Connector by Microsoft version 28.0.46665.48257
"External File Storage Impl."(CodeUnit 9455).ListDirectories line 4 - System Application by Microsoft version 28.0.46665.48758
"External File Storage"(CodeUnit 9454).ListDirectories line 2 - System Application by Microsoft version 28.0.46665.48758
"File Account Browser Mgt."(CodeUnit 9458).BrowseFolder line 8 - System Application by Microsoft version 28.0.46665.48758
"Storage Browser"(Page 9455).BrowseFolder line 2 - System Application by Microsoft version 28.0.46665.48758
"Storage Browser"(Page 9455).BrowseFileAccount line 2 - System Application by Microsoft version 28.0.46665.48758
"File Account Impl."(CodeUnit 9451).BrowseAccount line 10 - System Application by Microsoft version 28.0.46665.48758
"File Accounts"(Page 9450)."StorageBrowser - OnAction"(Trigger) line 2 - System Application by Microsoft version 28.0.46665.48758

Once all issues are cleared, we can proceed to the next step of the setup. Choose Navigate -> File Scenarios. More details: Enable external storage for document attachments

Choose Assign scenarios

Choose OK.

Choose Yes.

After you confirm, the External Storage Setup page opens. Set up how to offload attachments:

Turn on the Enabled toggle for the Document Attachments scenario. This setting confirms that Business Central offloads attachments to the specified storage. Business Central displays a warning that using external storage is at your own risk and that you’re responsible for managing and backing up the files. Read the warning, and then choose Yes to proceed. The Document Attachments scenario is now active.

Select Enable.

Choose Yes.

You are about to enable External Storage.

When this feature is enabled, files will be stored outside the Business Central service boundary. Microsoft does not manage, back up, or restore data stored in external storage.

You are responsible for the configuration, security, compliance, backup, and recovery of all externally stored files. This feature is provided as-is, and you enable it at your own risk.

Do you want to continue?

Done.

In the Root folder field, choose a folder in your external storage where you store attachments for this Business Central environment. You can only select an existing container/folder. Business Central automatically organizes subfolders in this root using a structured hierarchy of environment, company, table, and so on, to group files by their source record type. For example, it stores attachments for records in the Sales Header table (sales orders, and so on) in a Sales Header folder in your storage.

To specify whether to delete an attachment record in your external storage when someone deletes the record in Business Central, turn on the Delete External File on Attachment Delete toggle. If you disable this option, deleting an attachment in Business Central removes the link in Business Central, but the file remains in external storage until you manually remove it.

Review your settings, and then choose Close to complete the scenario setup. The Document Attachments feature is now linked to your external storage account. From this point on, new attachments you add to records in Business Central are stored in the external location instead of the Business Central database.

For example, I uploaded an attachment to Sales Orders.

This file is automatically saved to the following folder in SharePoint.

Root Folder -> Current Environment Hash -> Table Name

It appears that Business Central automatically appends a GUID to the filename to ensure uniqueness and prevent duplicates.

In addition, there are three powerful additional features.

Storage Sync: Run the synchronization job to move document attachments to or from external storage.

Migrate Files: Migrate all document attachments from the previous environment/company folder to the current environment/company folder.

Document Attachments: Open the document attachment list with information about the external storage.

More details: Store document attachments in external file storage

It offers incredibly powerful standard features, I highly recommend giving it a try!😁

PS: Dynamics 365 Business Central Blog Series: Integrate Business Central with SharePoint

Note: If you do not see any records when assigning the document attachments scenario.

Please check if External Storage – Document Attachments is already installed in your environment. In my tests, this extension is not automatically installed in upgraded environments.

We have to use the direct URL to install it. In address bar, append following to the base business central URL. More details: Dynamics 365 Business Central: Can we uninstall Microsoft (First-party) extensions and how to install them back?

?aid=FIN&page=2503&filter=%27ID%27%20IS%20%27<App ID>%27&signInRedirected=1

Then replace part with the AppSource Extension’s App Id. For example,

?aid=FIN&page=2503&filter=%27ID%27%20IS%20%275f2e93a0-6083-4718-b05a-7ac89be5644d%27&signInRedirected=1

Great.

Done.

END

Hope this will help.

Thanks for reading.

ZHU