diff --git a/app/src/main/java/eu/faircode/email/MessageHelper.java b/app/src/main/java/eu/faircode/email/MessageHelper.java
index f7b0fd4cab..5b9cab4572 100644
--- a/app/src/main/java/eu/faircode/email/MessageHelper.java
+++ b/app/src/main/java/eu/faircode/email/MessageHelper.java
@@ -31,7 +31,6 @@ import androidx.preference.PreferenceManager;
 import com.sun.mail.gimap.GmailMessage;
 import com.sun.mail.iap.ProtocolException;
 import com.sun.mail.imap.IMAPFolder;
-import com.sun.mail.imap.IMAPInputStream;
 import com.sun.mail.imap.IMAPMessage;
 import com.sun.mail.imap.protocol.IMAPProtocol;
 import com.sun.mail.util.ASCIIUtility;
@@ -2332,12 +2331,8 @@ public class MessageHelper {
                             break;
                         }
                     }
-                } else if (content instanceof String) {
-                    String text = (String) content;
-                    String sample = text.substring(0, Math.min(200, text.length()));
-                    Log.e("Mixed string=" + sample);
                 } else
-                    Log.e("Mixed type=" + (content == null ? null : content.getClass().getName()));
+                    throw new IllegalArgumentException("Multipart=" + (content == null ? null : content.getClass().getName()));
             }
 
             if (part.isMimeType("multipart/signed")) {
@@ -2452,16 +2447,8 @@ public class MessageHelper {
                 Object content = part.getContent(); // Should always be Multipart
                 if (content instanceof Multipart)
                     multipart = (Multipart) part.getContent();
-                else if (content instanceof String) {
-                    String text = (String) content;
-                    String sample = text.substring(0, Math.min(200, text.length()));
-                    throw new ParseException(content.getClass().getName() + ": " + sample);
-                } else if (content instanceof IMAPInputStream) {
-                    String text = Helper.readStream((IMAPInputStream) content);
-                    String sample = text.substring(0, Math.min(200, text.length()));
-                    throw new ParseException(content.getClass().getName() + ": " + sample);
-                } else
-                    throw new IllegalArgumentException(content.getClass().getName());
+                else
+                    throw new IllegalArgumentException("Multipart=" + (content == null ? null : content.getClass().getName()));
 
                 boolean other = false;
                 List<Part> plain = new ArrayList<>();