Power Platform Community Forum Thread Details

Hi everyone,

we’re experiencing an issue with the Dynamics 365 Business Central data connector.

Up until about two months ago, we were able to display item pictures in a gallery image control in Power Apps. The images come from BC365 and are exposed through a custom API.

In the gallery image control, we used the following expression:

Codice

"data:image; application/octet-stream; base64," & LookUp('items (xxx/xxx/v2.0)', no = "item_code").picture

Now the images no longer appear, any error show and I can’t figure out why.
No changes have been made to our Power Apps configuration or to the BC365 API code. We also reattached the connector and refreshed the data source, but the issue persists.

In the BC365 AL API code, the field is exposed as:

Codice

field(picture; Rec.Picture)
{
    Caption = 'Picture';
}

Has anyone experienced something similar or has any suggestions?
Have any changes been made by Microsoft?
Is it necessary to create a custom connector? If so, could you point me in the right direction on where to start?"

Thanks in advance

This is almost certainly a change on the Business Central side, not Power Apps, which is exactly why nothing in your app changed but the images stopped.
Here's the likely cause. When you expose a Media/Picture field in an API page (your field(picture; Rec.Picture)), Business Central doesn't actually hand back the raw base64 in that property. Its standard model exposes pictures as a media stream you fetch through a separate read link (content@odata.mediaReadLink), not inline. So if a platform update changed how your Media field serializes, your .picture would stop returning the base64 string you were concatenating, the data URI becomes invalid, and the image control just fails silently. No error, no image, which matches what you're seeing.
Quickest way to confirm: temporarily set a label's Text to LookUp('items (...)', no = "item_code").picture and look at what comes back. If it's empty, a GUID, or a URL instead of a long base64 string, that's your answer, the field content changed underneath you.
The fix is on the BC API, and no, you don't need a custom connector for it. Instead of relying on the Media field's default output, add an explicit text field in your API page that reads the picture blob into an InStream and Base64-encodes it, plus a small field for the MIME type. Then point your Power Apps data URI at that text field. That guarantees real base64 every time, regardless of how BC serializes Media going forward. The eOne "Business Central item image web service" write-up is a good reference for exactly this pattern.
Two smaller things while you're in there:

Your data URI string is slightly malformed: "data:image; application/octet-stream; base64,". The valid form has no spaces and a single media type, like "data:image/jpeg;base64," (or build it from the MIME field you expose). It likely worked before on lenient parsing, but worth cleaning up.
If you'd rather not touch the AL, the alternative is a Power Automate flow that calls the picture's mediaReadLink with auth, returns base64 to the app, and you bind the gallery to that. More moving parts, so I'd try the API field first.

Short version: BC changed how the Media field comes through the API, your .picture isn't base64 anymore, and the clean fix is exposing a dedicated base64 text field from the API rather than building a custom connector.
Hope that helps.