diff --git a/e-invoicing-domain/src/main/kotlin/net/codinux/invoicing/mail/MailReader.kt b/e-invoicing-domain/src/main/kotlin/net/codinux/invoicing/mail/MailReader.kt
index eeedc46..cc2c533 100644
--- a/e-invoicing-domain/src/main/kotlin/net/codinux/invoicing/mail/MailReader.kt
+++ b/e-invoicing-domain/src/main/kotlin/net/codinux/invoicing/mail/MailReader.kt
@@ -122,8 +122,9 @@ class MailReader(
 
                 if (invoice != null) {
                     val filename = File(part.fileName)
-                    val file = File.createTempFile(filename.nameWithoutExtension, filename.extension).also { file ->
+                    val file = File.createTempFile(filename.nameWithoutExtension, "." + filename.extension).also { file ->
                         part.inputStream.use { it.copyTo(file.outputStream()) }
+                        file.deleteOnExit()
                     }
 
                     return MailAttachmentWithEInvoice(part.fileName, mediaType, invoice, file)