Accepting Files Via Email

Inboxes can be used to receive files from email attachments. Your site provides settings that affect whether and how an Inbox handles incoming emails.

Enabling Email Uploads to an Inbox

When your Inbox allows uploads via email, any application, system, or person can send files directly to your inbox. When the behavior is enabled, a unique email address is generated for this inbox. Anyone with the address can then upload by sending an email attachment, unless you restrict the allowed senders to specific addresses or domains.

CRM, ERP, or HRMS applications can upload files directly to the inboxes using the email address. Users can forward emails with attachments to this email address in the To, Cc, or Bcc fields.

Files attached to each email are stored in the inbox folder. Inboxes route email uploads into automatic subfolders by default. Files with the same name follow the site's overwrite behavior. If the email body contains embedded images or images in the email signature, those images are uploaded to the inbox along with the other email attachments.

If you enable the Save inbound email body content to a text file setting for your inbox, the body of each incoming email is stored in a file with the name you provide.

Message Size Limits

Inboxes accept email messages as large as 40MB. The limit applies to the total size of the email, including any attachments or embedded images. If an email larger than 40MB is sent to your inbox, the sender receives the message "Your message is larger than the size limit for messages. Please make it smaller and try sending it again.".

The 40MB limit cannot be raised, because it is enforced by our mail services provider. If your contact needs to deliver a file larger than 40MB, enable web uploads for your inbox and direct your contact to upload through a web browser. If the message is large due to multiple attachments, the contact can send multiple emails to your inbox with separate attachments that each fit below the 40MB size limit.

Some mail providers enforce size limitations below 40MB. GMail and Yahoo Mail limit messages to 25MB, and iCloud Mail has a limit of 20MB. Check the specific documentation for the mail provider if your contact receives an error related to the message size when sending to your inbox.

Pre-Requisites for Inbox Email Uploads

Your inbox cannot require a password and allow email uploads, because the sender cannot provide a password via email. To limit uploads to the right people, enable inbound email authentication for your site, then whitelist the addresses or domains you want to allow.

Inboxes cannot collect registration information through email, so you cannot require registration on an Inbox that allows email uploads. If your Inbox requires registration, you cannot enable email uploads.

Interactions with Other Features

Inboxes are always associated with a folder in your Files site, so folder settings and site settings affect how files emailed to the inbox are stored. The Inbound Emails Log describes what happened with each received email, so you can determine how and why particular files were affected by your configuration.

Email Upload Subfolder Paths

Inboxes route email uploads into automatic subfolders by default. This prevents later submissions from overwriting earlier ones when filenames repeat.

You can disable this behavior with the Do not create subfolders for inbound email uploads to this inbox setting. We do not recommend disabling automatic subfolders. Repeated filenames are common in email-based workflows, and if your site allows overwrites, new files with the same name overwrite old files.

Email uploads support a destination path template. This template defines what name is used for the automatic subfolders. Build the template from literal folder names plus placeholders. Placeholders insert values from the inbound email. Supported placeholders include the sender's display name {{name}}, the sender's email address {{email}}, the sender's email domain {{email_domain}}, and time-based placeholders.

The final stored path still follows the site's Overwrite behavior. If two files land in the same destination folder with the same name, the overwrite setting determines the outcome.

Overwrite Behavior

Uploading files via email with duplicate names follows the site's Overwrite behavior. If the setting is Automatically append numbers to conflicting file names, duplicate files uploaded through email to the inbox are automatically renamed. If the inbox is configured to store the email body in a file, that file is also not overwritten.

If the site's Overwrite behavior setting is Allow files to be overwritten, but ask first, duplicate file names are overwritten. The system cannot prompt the email uploader for permission on each file.

Automatically Renaming Uploads

Enabling the feature to automatically rename files uploaded to a folder also affects files saved through the email interface. This applies to all files received as email attachments. If the Save inbound email body content to a text file setting is enabled, the file created to hold the email body content is also automatically renamed.

Organize Files Into Subfolders

If you enable the feature to automatically organize uploads into subfolders for the inbox folder, any successfully uploaded attachments are placed into a subfolder of the inbox folder.

This folder setting is separate from the Inbox setting that routes email uploads into subfolders using a destination path template.

If the Save inbound email body content to a text file setting is enabled, the file created to hold the email body content is also stored in a subfolder of the inbox folder.

Limiting What Can Be Uploaded

Any rules that limit the types of files that can be uploaded to a folder also apply to email attachments sent to the inbox. This includes limiting uploads by filename length, by file extension, or by regular expression.

If the Save inbound email body content to a text file setting is enabled, the file created to hold the email body content is not stored if it conflicts with a rule that limits the files that can be uploaded to the folder. For example, if you configure your incoming email body content filename to be incoming-email.txt and you blacklist the TXT extension, the body is not saved.

Disabling Web Access

If your inbox is integrated into an automated workflow where a third-party application or system uploads files via email, the best practice is to use the inbox exclusively for email and block web access.

To receive files only through email and prevent web uploads, activate the Disallow web browser uploads to this inbox setting. This disables all web access to the inbox.

Restricting Who Can Email Files to an Inbox

A site administrator must enable Inbound email authentication for your site to enforce email restrictions. The allowed email addresses or domains are verified via SPF, DKIM, and DMARC to prevent spoofing or other misuse. Emails that do not pass these checks are discarded by the system.

The Allow only these senders to upload via email setting limits which email addresses can upload files into the Inbox. With this setting enabled, uploads to the inbox are restricted to your chosen sender email addresses or email domains. Attachments from all other senders are discarded by the system. Your list can include up to 10 email addresses or email domains.

Review your Inbound Email Logs to see the results of each email received.

Send an Email Receipt to Uploaders

Enable the Notify senders on successful upload via Email setting to send an acknowledgment receipt email to the sender whenever a file is successfully stored from an inbound email to the Inbox.

No Email for Failed Uploads

Uploaders do not receive an email acknowledgement about files that failed to upload. Files can fail to upload due to recipient restrictions, because of folder settings that restrict uploads, or because your Inbox folder is on a Remote Server Mount that was offline when the email was received. Review your Inbound Email Logs to see the result of each received email.