re : my recipients can see some of the blind copy addresses but not all. This is most likely down to something the server is doing or not doing. Q: What server are you using to send emails? gmail, yahoo, comcast etc Q: Those recipients that are seeing some bcc'd email address, are they all on the same server. eg: the latter part of email address is the same or they all go through a particular server eg: outlook

re : when they click on 'reply all' it goes to all that were blind copied. Are they all using Thunderbird email client? After clicking on 'Reply-all', can they see all the individual email addresses before they send?

the recipient who told me about it is using gmail. When she clicked on reply all it showed two of the blind copied addresses but sent it to another, that had not been displayed but was in the blind copy, as well as the ones displayed. I am using sky email which uses yahoo. if i go to the sky website to log into my emails i can send blind copies there and when they arrive reply all is not an option