diff --git a/app/src/main/java/eu/faircode/email/FragmentCompose.java b/app/src/main/java/eu/faircode/email/FragmentCompose.java
index 362c7f32ad..4035769b12 100644
--- a/app/src/main/java/eu/faircode/email/FragmentCompose.java
+++ b/app/src/main/java/eu/faircode/email/FragmentCompose.java
@@ -1288,7 +1288,7 @@ public class FragmentCompose extends FragmentBase {
                     os.write(buffer, 0, len);
 
                     // Update progress
-                    if (attachment.size != null)
+                    if (attachment.size != null && attachment.size > 0)
                         db.attachment().setProgress(attachment.id, (int) (size * 100 / attachment.size));
                 }