Hi ,
please support to fix below issues generated while attaching some files in attchments in editable email notification(email-ext plugin) at job .

issue1: ERROR: Interrupted in processing attachments: null
issue2: ERROR: Could not send email as a part of the post-build publishers.

cases and generated issues are given below for your reference.

Job configuration:
Matrix job
Variant 1 2 3
Select “Trigger each configuration”

Case1:
Enable Attachment – add some files here
Disable archive artifacts option
Save and Build job:
Result: ISSUE
received all 3 mails for all 3 varaints
But one variant mail only didn't attach files and msg at console
ERROR: Interrupted in processing attachments: null

Case2:
Enable Attachment – add some files here which are available at archive artifacts also.
Enable archive artifacts and keep some files here .
Save and Build job
Results: ISSUE: Only one of variants got this below error and no email generated.
ERROR: Could not send email as a part of the post-build publishers.
javax.mail.MessagingException: IOException while sending message;
nested exception is:
java.io.IOException
at com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:1141)
at javax.mail.Transport.send0(Transport.java:195)
at javax.mail.Transport.send(Transport.java:124)
at hudson.plugins.emailext.ExtendedEmailPublisher.sendMail(ExtendedEmailPublisher.java:282)
at hudson.plugins.emailext.ExtendedEmailPublisher._perform(ExtendedEmailPublisher.java:265)
at hudson.plugins.emailext.ExtendedEmailPublisher.perform(ExtendedEmailPublisher.java:225)
at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:36)
at hudson.model.AbstractBuild$AbstractRunner.perform(AbstractBuild.java:697)
at hudson.model.AbstractBuild$AbstractRunner.performAllBuildSteps(AbstractBuild.java:672)
at hudson.model.AbstractBuild$AbstractRunner.performAllBuildSteps(AbstractBuild.java:650)
at hudson.model.Build$RunnerImpl.cleanUp(Build.java:171)
at hudson.model.Run.run(Run.java:1448)
at hudson.matrix.MatrixRun.run(MatrixRun.java:146)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:238)
Caused by: java.io.IOException
at hudson.remoting.FastPipedInputStream.read(FastPipedInputStream.java:175)
at hudson.remoting.FastPipedInputStream.read(FastPipedInputStream.java:151)
at javax.activation.DataHandler.writeTo(DataHandler.java:293)
at javax.mail.internet.MimeBodyPart.writeTo(MimeBodyPart.java:1476)
at javax.mail.internet.MimeBodyPart.writeTo(MimeBodyPart.java:865)
at javax.mail.internet.MimeMultipart.writeTo(MimeMultipart.java:462)
at com.sun.mail.handlers.multipart_mixed.writeTo(multipart_mixed.java:103)
at javax.activation.ObjectDataContentHandler.writeTo(DataHandler.java:869)
at javax.activation.DataHandler.writeTo(DataHandler.java:302)
at javax.mail.internet.MimeBodyPart.writeTo(MimeBodyPart.java:1476)
at javax.mail.internet.MimeMessage.writeTo(MimeMessage.java:1772)
at com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:1099)
... 14 more

Case3:
Disable attachment
Enable archive atrtifacts
No issue. All email generated without attachment.