Haruno asks the antivirus on the PC to check every attached file before a message can be sent. The chip shows the result, and a file reported as malware blocks the send.
Mac appNot availableThe Mac app checks what a file really is and refuses programs, but it does not scan files for malware.
Windows appAvailableUses Microsoft Defender. With another antivirus in charge, files go through marked Not scanned.
Before Haruno uses a file you attached, it asks the antivirus on your PC to look at it. The antivirus is Microsoft Defender, which comes with Windows. The result shows on the file's chip, above the message box.
The check happens on your PC. Haruno does not send the file, or any fingerprint of it, anywhere for this. Defender's own cloud features are set by the owner of the PC.
What you see on a chip
The check runs in the background as soon as you attach a file, so the message box stays usable. It usually takes less than a second. The first check after the PC has been idle can take longer.
A clean file shows nothing extra. The others are still being checked, or could not be scanned.
The chip says
What it means
Can you send?
Nothing extra
The antivirus found nothing.
Yes
Checking for malware…
The check is still running.
Not yet. The message waits for the chip.
Not scanned: no scanner available
There is no antivirus to ask.
Yes. The file is marked, and the antivirus on the PC still looks at it when it is opened.
Blocked: malware found. Remove it.
The antivirus reported the file as malware.
No. Remove the chip with ×.
Not checked. Retry.
The check did not finish. A ↻ button tries again.
No, until a retry succeeds or you remove the chip.
Not checked: definitions out of date. Retry.
Defender's virus definitions are more than seven days old, or Defender will not say how old they are.
No. Update Windows or Defender, then retry.
A blocked file, and a file that could not be checked and can be retried.
When there is no antivirus to ask
If the PC uses a different antivirus, Windows usually switches Defender off. Haruno then has nothing to ask, so it lets the file through marked Not scanned: no scanner available. If it blocked every file in that case, anyone with another antivirus could not attach anything. The antivirus the PC does have still looks at the file when it is opened.
If Defender is on but cannot answer, for example because its definitions are too old or the scan failed, Haruno does not guess. It blocks the send and offers a retry.
Where the check runs
Attachments are checked when you attach them, and again for the copy Haruno makes for the chat. If the file has not changed, the first answer is reused.
Summaries on the Files page are checked before Haruno reads the file.
Files added to a connector page, such as the Portfolio, are checked before they are accepted.
What it does not cover
Clean does not mean safe
"Clean" means the antivirus on this PC did not recognise the file. It is not a guarantee. A file on Defender's exclusion list is reported clean without being looked at, and an encrypted archive cannot be opened to look inside.
A file that sits inside the project folder is checked when you attach it, but not again when you send. If you replace it after the chip turned clean, Haruno does not look at it again.
Files Haruno writes itself are not scanned. Open hands the file to Windows, whose own protection applies.
What is recorded
Haruno keeps a small local record of each detection, each file let through unscanned and each check that could not be made. It does not hold file names, paths or fingerprints, so it can be sent with a support request. Nothing is reported to a server.
What to tell a customer
Attachments are checked on their own PC, by the antivirus they already have. Nothing about the file leaves the computer for this check.