Block and allow senders

Block an address or a whole domain, keep trusted senders out of Junk, and report a message to the SipherMail team.

Block a sender#

  1. Open a message.
  2. In the message menu, choose Block sender.
  3. In the Block Sender window, optionally tick Block entire domain to block every address at that domain.
  4. Optionally tick Move existing emails to Junk to also move mail you already have from that address or domain.
  5. Optionally add a reason. It is only for your own reference.
  6. Select Block Sender.

From then on, mail from that address or domain goes straight to Junk when it arrives, so you can still find it and use Not spam if you blocked it by mistake. The confirmation tells you how many existing messages were moved.

Existing mail is moved from your folders except Sent, Drafts, Trash and Junk. One block moves up to 500 messages. If there are more, the confirmation says some remain, and you can block again to continue.

If you have a very large number of blocked senders (more than about 80 domains or a few thousand addresses), the oldest entries that do not fit in your mail filter are discarded instead of moved to Junk.

Unblock a sender#

  1. Open Settings > Spam & Filters.
  2. Find the Allowed and blocked senders card and look under Blocked.
  3. Select the bin icon beside the sender.

A block set by an administrator or by your organisation cannot be removed here, and your own safe senders do not override it. Those blocks reject or discard mail instead of moving it to Junk.

You can also block from Subscriptions. See Manage subscriptions.

Safe senders#

A safe sender skips Junk. Two ways to add one:

  • Open a message in Junk and choose Not spam.
  • On Settings > Spam & Filters, type a full address, or a domain that starts with @, and select Add.

Safe senders are kept per mailbox. A safe sender skips Junk only when the message passes authentication (DMARC passes, or SPF or DKIM matches the From domain) and is not flagged as malware or phishing. A message that fails these checks is not let through by a safe sender entry.

Mark as spam#

Choose Mark as spam on a message. SipherMail asks you to confirm, then moves it to Junk.

Report a message#

Choose Report in the message menu, pick a Report Type and add details if you want. The types are Spam, Phishing Attempt, Malware/Virus, Scam and Inappropriate Content. The SipherMail security team reviews reports, and the sender may be blocked if the message is confirmed malicious.

Last updated 2 November 2026