How do I send an attachment only the recipient can open?
For occasional use a password-protected ZIP or a 365 share link with a password is usually enough. No full S/MIME needed.
Try this first
- 1Make a ZIP and set a password using your archive tool of choice. Pick one you do not send in the same mail.
- 2Send the password via a different channel: phone, SMS, or a messaging app. Never the same mail thread.
- 3Or: place the file on OneDrive and share with 'specific people' plus a link password.
- 4Ask the recipient to confirm they could open it before you delete the source file.
When to bring us in
If you do this daily and it gets messy, we will set up a clean flow; so colleagues do not have to invent passwords every time.
See also
- Our emails land in spam for some recipientsAlmost always an SPF, DKIM, or DMARC setting that is wrong or missing, or a sender name that mimics a well-known brand.
- Someone reports receiving phishing emails "from us"Read: spoofing. Someone is abusing your sender name, not necessarily your actual mailbox.
- An email bounces (NDR): delivery failedThe NDR text usually states the exact reason. Reading it is step one.
None of the above fits?
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Or skip the DIY entirely
Our Managed IT clients do not look these things up. One point of contact, a fixed monthly price, resolved within working hours.