I am using and have been using "Postbox", a desktop email client, to send and receive all my emails through my Live account on "Outlook.com" using IMAP. Everything has worked perfectly between "Postbox" and "Outlook.com" for several years and I haven't changed anything on my end. About two weeks ago, I started having problems. Now, when I put a single name or a group list into the Bcc field on my "Postbox" desktop email client and send that email through my outgoing SMTP server at "Outlook.com", the email goes through "Outlook.com" and "Outlook.com" moves all the names from the Bcc field to the TO field. I am assuming this has something to do with the new changes associated with the updated "Outlook.com/Outlook Mail" web mail process. Notes: When I do the same thing using "Gmail" for my outgoing SMTP server, my names stay in the Bcc field as they should. My Outlook.com web page now shows Outlook Mail in the top left corner. I am using imap-mail.outlook.com Port 993 and smtp-mail.outlook.com Port 587 for my servers. I tried switching to imap-mail.live.com and smtp-mail.live.com as one MS web site suggested regarding the new changes to Outlook Mail but those new setting would not connect. I tried using Mozilla Thunderbird instead of Postbox as my desktop email client and the same problem occurred in that the name in my outgoing Bcc field was put into the To field after the email was processed through Outlook.com. Based on all of the above, I believe the problem has something to do with the way the new Outlook Mail is trying to process names from the Bcc field in emails sent from my desktop email clients. I hope someone from MS can look into this problem and get back to us.

Correction: After further test, it appears that the Office 365 server will not send Bcc emails if you send using an email program. If you login using a browser, Bcc emails can be sent. I will test using Windows 10 Mail and Windows Live Mail.

Ron: I appreciate the advice. I have tried using names. I have tried using email addresses. I have tried using Postbox. I have tried using Thunderbird. I even tried creating a new alias account to see if that changed anything - it didn't. When I put an email address in the "To" field, another email address in the "Cc" field and two more email addresses in the "Bcc" field, the result is that the email addresses used in the "To" and "Cc" fields received emails from me and the email addresses used in the "Bcc" field never received my emails when I send from my SMTP server at Outlook.com. If I do the same thing and send the email using an SMTP server at Gmail.com, everything works great and all four emails are received properly. This problem started about the time my LIVE account was migrated from the web Outlook.com to the new Outlook Mail processes. Apparently most accounts like yours are working fine and a few like mine aren't. I have tried a lot of variations during my tests to pinpoint a particular scenario and nothing I do on my end ever changes the results. My situation seems to involve something that changed and is not working properly on the backend, and I do not think it is anything you or I will be able to resolve. Someone from MS technical services is needed. I thank you for your assistance.

When I am testing to find email bugs, I always use email addresses. This eliminates names not being in the address book (people). Spam filters have flagged emails with no address in the To field as spam for years. I have no problems sending with addresses in Bcc.

Ron: I appreciate your help and found something else that might help resolve the problem. I found another post in another forum where you told the person that a name has to be in the "To" field. So, I put a name in the "To" field and I put two names in the "Bcc" field and then sent the email. The result was that the email was sent to the name in the "To" field. However, NO email was ever received by the names that I put in the "Bcc" field. As I stated above, these problems only started after Outllok.com / Outlook Mail changed recently. Any help or thoughts would be appreciated.

Outlook.com Moving Addresses From Bcc Field to the TO Field When Email is Sent via Desktop Email Client

Anonymous

I am using and have been using "Postbox", a desktop email client, to send and receive all my emails through my Live account on "Outlook.com" using IMAP. Everything has worked perfectly between "Postbox" and "Outlook.com" for several years and I haven't changed anything on my end. About two weeks ago, I started having problems. Now, when I put a single name or a group list into the Bcc field on my "Postbox" desktop email client and send that email through my outgoing SMTP server at "Outlook.com", the email goes through "Outlook.com" and "Outlook.com" moves all the names from the Bcc field to the TO field. I am assuming this has something to do with the new changes associated with the updated "Outlook.com/Outlook Mail" web mail process.

Notes:

When I do the same thing using "Gmail" for my outgoing SMTP server, my names stay in the Bcc field as they should.
My Outlook.com web page now shows Outlook Mail in the top left corner.
I am using imap-mail.outlook.com Port 993 and smtp-mail.outlook.com Port 587 for my servers. I tried switching to imap-mail.live.com and smtp-mail.live.com as one MS web site suggested regarding the new changes to Outlook Mail but those new setting would not connect.
I tried using Mozilla Thunderbird instead of Postbox as my desktop email client and the same problem occurred in that the name in my outgoing Bcc field was put into the To field after the email was processed through Outlook.com.
Based on all of the above, I believe the problem has something to do with the way the new Outlook Mail is trying to process names from the Bcc field in emails sent from my desktop email clients.

I hope someone from MS can look into this problem and get back to us.

Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

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Answer accepted by question author

Anonymous

Thank you for the thorough feedback Laurel. The post-mortem investigation (as we call it) into the support escalation is underway.

Glad that the fix has reached you. For John and everyone else, the fix has reached about 75% of servers now. There will be a long tail of stragglers but we are working to reach 100% by the end of next week.

Regards,

Sean

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50 additional answers

Anonymous

2016-05-31T03:27:13+00:00

Correction:

After further test, it appears that the Office 365 server will not send Bcc emails if you send using an email program.

If you login using a browser, Bcc emails can be sent.

I will test using Windows 10 Mail and Windows Live Mail.
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Anonymous

2016-05-30T15:04:49+00:00

Ron:

I appreciate the advice.

I have tried using names. I have tried using email addresses. I have tried using Postbox. I have tried using Thunderbird. I even tried creating a new alias account to see if that changed anything - it didn't. When I put an email address in the "To" field, another email address in the "Cc" field and two more email addresses in the "Bcc" field, the result is that the email addresses used in the "To" and "Cc" fields received emails from me and the email addresses used in the "Bcc" field never received my emails when I send from my SMTP server at Outlook.com. If I do the same thing and send the email using an SMTP server at Gmail.com, everything works great and all four emails are received properly.

This problem started about the time my LIVE account was migrated from the web Outlook.com to the new Outlook Mail processes. Apparently most accounts like yours are working fine and a few like mine aren't. I have tried a lot of variations during my tests to pinpoint a particular scenario and nothing I do on my end ever changes the results.

My situation seems to involve something that changed and is not working properly on the backend, and I do not think it is anything you or I will be able to resolve. Someone from MS technical services is needed.

I thank you for your assistance.
Was this answer helpful?

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Anonymous

2016-05-30T02:15:12+00:00

When I am testing to find email bugs, I always use email addresses.

This eliminates names not being in the address book (people).

Spam filters have flagged emails with no address in the To field as spam for years.

I have no problems sending with addresses in Bcc.
Was this answer helpful?

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Anonymous

2016-05-29T15:04:50+00:00

Ron:

I appreciate your help and found something else that might help resolve the problem.

I found another post in another forum where you told the person that a name has to be in the "To" field.

So, I put a name in the "To" field and I put two names in the "Bcc" field and then sent the email.

The result was that the email was sent to the name in the "To" field. However, NO email was ever received by the names that I put in the "Bcc" field.

As I stated above, these problems only started after Outllok.com / Outlook Mail changed recently.

Any help or thoughts would be appreciated.
Was this answer helpful?

0 comments No comments