We're using 2013R2.
For one particular email we are trying to update the BodyHtml field of the MailMessage class and we get the following stack trace:
--- Start Exception Stack ---
Rebex.Mail.MailException: Cannot change read-only message.
at Rebex.Mail.AttachmentBase.SetContent(String text, String mediaType)
at Rebex.Mail.MailMessage.set_BodyHtml(String value)
at pf.MCC.Server.Common.Models.RebexEmail.Load(Stream stream, String id)
at pf.MCC.Server.Common.Models.Store.SaveNewMediaItem(NewMailMessage newMailMessage)
--- End Exception Stack ---
Normally there is no issue... just this one email. How does this property get into the read-only state and is there anyway to override it?
A bit more information. It appears there are some kind of issues with the signature. The message when trying to open the email in Exchange is: The signature is invalid because you have either distrusted or not yet chosen to trust the following Certificate Authority".