DirectAdmin's SPAM Filters can reject or filter messages above a configured size. This applies to the full encoded message, including headers and attachments, not just the attachment's size on disk.
Set a size filter
- Select the receiving domain in DirectAdmin.
- Open E-mail Manager → SPAM Filters.
- Choose the size option and enter the limit in the unit displayed by the panel. DirectAdmin commonly requests kilobytes; do not enter a megabyte value into a kilobyte field.
- Save the filter and review what happens to matching mail: it may be dropped or sent to the spam folder.
- Test with a harmless message before relying on the rule.
These filters apply across the selected domain's mailboxes. They are separate from the server's maximum message size and do not replace malware scanning. Attachment encoding makes the transmitted message larger than the original files, so leave room for encoding and headers.
If legitimate mail is missing
Review the spam folder where available and ask the sender for the full message size or delivery error. Raise or remove the filter if appropriate. Removing it cannot recover a message that was already dropped; ask the sender to resend. For very large files, use a trusted file-sharing link.
For the separate Hosted Email product, use its own controls or contact support rather than following DirectAdmin instructions.
