Understanding Email Headers with analysis status

After analyzing the email attachment/URL for threats, Intelligent Sandbox updates adds these headers of the respective emails with the observations, and sends the emails to the configured relay host.

Header	Values
`X-ATD-FILENAMES`	Lists the names of all attachments/URLs of the email separated by comma(,).
`X-ATD-ALTFILENAMES`	Lists the alternate names of scanned attachments that have the same hash value as determined during the earlier scans. For example, if after scanning a file (file1), another attachment with the same hash but a different file name (file2) is detected, the `X-ATD-ALTFILENAMES` header is added with the value file1, file 2.
`X-ATD-FILEHASHES`	Adds the hashes of all email attachments/URLs. For example, MD5 , SHA-256.
`X-ATD-FILEVERDICTS`	Adds the verdict for each email attachment/URL that was submitted for analysis. 5 — Very high (risk) 4 — Malicious 3 — Likely to be malicious 2 — Low activities 1 — Very low activity 0 — Informational -1 — Clean -2 — Failed to scan (because of unsupported file type) -3 — Scan Timed out -4 — Filtered by the File Type Configuration -5 — Filtered by File Filtering Rules
`X-ATD-VERDICT`	Adds the overall verdict for an email. 5 — Very high (risk) 4 — Malicious 3 — Likely to be malicious 2 — Low activities 1 — Very low activity 0 — Informational -1 — Clean -2 — Failed to scan (because of unsupported file type) -3 — Scan timed out -6 — No file attachments were scanned -7 — Silent Mode (When Intelligent Sandbox is set to disable file scanning, where the emails attachments are not scanned and only email count is incremented for every email) -8 — Intelligent Sandbox is too busy to service new scanning requests. At least one attachment has not been scanned and does not have a cached result (see `X-ATD-TOOBUSY`) -100 — Intelligent Sandbox failed to receive or deliver the emails
`X-ATD-SILENTMODE`	Adds the value of 1 if an email was scanned in silent mode. Otherwise this header is not added.
`X-ATD-TOOBUSY`	Adds this header to all messages that pass through Intelligent Sandbox while it is: processing new attachments/URLs for scanning configured in Email pass-through mode.