Hi d_radulova,
The businesscard field is formatted as Multiple Line of Text, just like we saw in note(annotation) entity's documentbody field.
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However, as you said and from my test, it's not base64 string like note or attachment,
instead CRM will generate a reference link for image file, currently I failed to scan a card due to capacity issue.(no AI Builder)
You could try methods below to update the businesscard field to remove image link:
1. Download CRMRestBuilder solution and import it into your Marketing application, it'll generate script code automatically.
https://github.com/jlattimer/CRMRESTBuilder
2. Run updateRecord (like Xrm.Page or executionContext)
https://docs.microsoft.com/en-us/powerapps/developer/model-driven-apps/clientapi/reference/xrm-webapi/updaterecord
(I tested it with a converted base64 string to update lead businesscard field and set it to empty field after base64 string didn't work, update operation is supported, while I found form won't render image with base64 string directly)
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Methods above are front-end with script code,
you could also try an on-demand workflow to clear the field manually without code.
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Supplement:
Hi d_radulova,
Now the feature works in my environment.
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It seems that CRM will concat data:image/jpeg:base64 prefix with converted base64 string data and set the result as src to image tag,
so the final conclusion is that image file is actually formatted as base64 string data, and currently there was no response when I click Business Card section to test whether it could give a prompt like entity image, please run workflow or script code to remove it manually.
Regards,
Clofly