The recipient must be registered in advance in "encrypt destination conditions" in PwMailExt.
Otherwise, decryption will fail.
If decryption fails even though it has been registered in "encrypt destination conditions",
Please check again whether the email address conditions are correct and whether the password is correct.
If decryption still fails, please check with the sender to see if the email was sent in plain text.
The iOS version of PwMailExt does not support HTML emails. Also, only image files are supported as attachments.