Attach header files to Email via Email Purchase Order button; 2025R2

Without digging in real deep, I would suggest verifying PXProtectedAccess behavior. I’ve always created the protected access class as a second-order extension. Pretty sure that’s a requirement.

(docs)

Thanks ​@darylbowman ; gave me something else to look at.  Getting closer, this now almost works.

When the button is clicked the email is created and goes into pending processing; the files aren’t there, but if you cancel sending they immediately populate. Gather I’m injecting this this with the wrong timing.

using PX.Data;
using PX.Objects.CR;
using PX.Objects.PO;
using System;
using System.Linq;

namespace Customizations
{
    public class CREmailActivityMaint_Extension
        : PXGraphExtension<CREmailActivityMaint>
    {
        protected void _(Events.RowPersisting<CRSMEmail> e)
        {
            if (e.Row == null)
                return;

            // Only process PO-related emails
            if (e.Row.RefNoteID == null)
                return;

            // Find related PO
            POOrder order =
                PXSelect<
                    POOrder,
                    Where<
                        POOrder.noteID,
                        Equal<Required<POOrder.noteID>>
                    >
                >
                .Select(Base, e.Row.RefNoteID);

            if (order == null)
                return;

            // Get PO attached files
            Guid[] poFiles =
                PXNoteAttribute
                    .GetFileNotes(Base.Caches<POOrder>(), order)
                    ?.ToArray();

            if (poFiles == null || poFiles.Length == 0)
                return;

            // Existing email files
            Guid[] emailFiles =
                PXNoteAttribute
                    .GetFileNotes(e.Cache, e.Row)
                    ?.ToArray()
                ?? new Guid[0];

            // Merge without duplicates
            Guid[] merged =
                emailFiles
                    .Union(poFiles)
                    .Distinct()
                    .ToArray();

            // Attach to email
            PXNoteAttribute.SetFileNotes(
                e.Cache,
                e.Row,
                merged);

            // Force row dirty state
            e.Cache.SetValueExt<CRSMEmail.subject>(
                e.Row,
                e.Row.Subject + "");

            e.Cache.Update(e.Row);
        }
    }
}

You could try overriding the persist method instead.