The Underscore Folder

Your site includes a virtual, system-controlled folder named _ (underscore). This folder is not included in listings of your site's root folder, but is accessed as though it were located in your site's root folder. Snapshots, Remote Servers, Child Sites, and Connected Sites use the underscore folder to provide access to their contents.

Only Site Administrators can browse the top-level underscore folder, and you cannot grant ordinary folder permissions to it. Access to a particular folder inside it follows the rules of the feature that owns that folder. For example, a snapshot's creator can access their own snapshot folder without being a Site Administrator.

Site administrators cannot make changes directly in the underscore folder because it is system-controlled. Automations and Folder Settings are not supported for the underscore folder itself. The subfolders of the underscore folder are used by the Snapshots feature, as well as for browsing any defined Remote Servers, Child Sites, or Connected Sites for your site. Some folders within those feature folders can be modified, such as the folder for an Snapshot that isn't finalized, or the contents of a Remote Server or Child Site.

Accessing the Underscore Folder

Site administrators can use any official Files.com SDK, the CLI application, FTP, SFTP, or the web interface to access the underscore folder at the path _.

Within the web interface, the Remote Servers page provides a shortcut to browse the server, and the Child Sites page lets you Browse an individual site.

The mobile application does not support access to the underscore folder.

Snapshot Folders

The Snapshots feature automatically creates separate sub-folders under the _/Snapshots folder to contain each Snapshot's content. Each folder is named with the ID of its associated snapshot.

The snapshot's creator and Site Administrators can list and read its sub-folder. Authorized visitors to an associated Share Link can read the files through that link. Other users cannot see or read the snapshot folder. The creator keeps read access to this independent copy even if their source-folder permissions change.

While a snapshot is not yet finalized, Site Administrators can change its files. The creator can also change them if they have Write permission somewhere on the site, within the same Workspace when Workspaces are in use. Finalization immediately prevents new changes for everyone, but a copy or move already transferring into the snapshot finishes and adds its file. See Snapshots Must Be Finalized for the transfer rules. Managing the snapshot record, including finalizing or deleting it, requires a Site Administrator.

Snapshot sub-folders are automatically removed from the _/Snapshots folder when the snapshot expires. If you revoke a snapshot Share Link before it expires, its files will remain in the underscore directory until the expiration date.

This data uses native Files storage in the default storage region of your site, and it counts against storage usage for your site.

Remote Server Folders

Configuring a Remote Server for your site automatically creates separate sub-folders under the _/RemoteServers folder which function as automatic mounts. Each folder is named with the ID of its associated server.

Your allowed actions in each _/RemoteServers folder will depend upon the permissions configured for the connection. If the credentials used for the Remote Server only provide list and download access, you will not be able to upload to that server using the underscore folder.

Each server's folder in the _/RemoteServers folder connects to the root folder of the corresponding remote server using the integration type configured for that server. For example, SFTP-based remote servers use the SFTP protocol, and Azure Blob-based remote servers use the Azure APIs. You can navigate in the usual ways to subfolders that you have access to on the remote server.

If you do not have access permission to the root folder of the remote server, you will receive an error when connecting to the server's folder under the _/RemoteServers folder. In the web interface, this might say "There was an issue getting the contents of this folder". Folder paths that do not have access permission cannot be interacted with. To access an FTP or SFTP server whose credentials are restricted to a subfolder, configure a Remote Mount for that subfolder. The web interface browser starts at the default home folder for FTP and SFTP servers, which can differ from the root exposed by the underscore path.

If a Remote Server's authentication expires or is revoked, its underscore folder cannot connect. Re-authenticate the Remote Server to restore access.

The data stored in the _/RemoteServers folder does not count against storage usage for your site because it is physically located on your external server.

Quarantine Folder

When Malware Scanning identifies an uploaded file as unsafe, it moves the file into the _/Quarantine folder, keeping the file's original path underneath it so an administrator can identify where it entered the site. The folder appears only after a file has been quarantined.

The _/Quarantine folder is locked down. You cannot configure folder settings or notifications anywhere beneath it, and no Sync or Automation can write into it. Site Administrators can download a copy or use the folder as a Sync source to send a copy elsewhere.

This data uses native Files storage and counts against storage usage for your site. The original files remain in quarantine indefinitely to preserve evidence for investigation, and cannot be released.

Child Site Folders

Each Child Site of your site can be accessed through a sub-folder of the _/Sites folder. Each sub-folder is named with the numeric ID of its associated site. Much like the Remote Server Folders, the child site folders function as automatic mounts to the root of each child site.

Site administrators of a parent site have unrestricted file access to each child site's sub-folder in the _/Sites folder. You can upload, download, delete, move, copy, preview, edit files with your site's office integration, and create folders in a child site's sub-folder.

Site administrators cannot configure any folder settings on or within a child site's sub-folder.

The data stored in _/Sites sub-folders is counted only once as storage usage, not on both the child site and the parent site.

Connected Site Folders

When your site is the Guest in a Connected Sites relationship, the Host appears at _/Sites/<host-site-id>, alongside any Child Sites. This folder opens the Host Partner's root folder, not the entire Host site.

Your Site Administrators receive access to this folder and can use the connected folders with your site's sharing, permissions, and automated workflows. Other people can receive access through the features your site configures. Those features belong to your site and follow its settings; the Host does not view or control them.

The Host Partner's permissions control every operation on the Host's files, including operations through your site's features and in any Remote Server Mounts within the shared folders. Unlike a Parent Site's access to a Child Site, being an administrator on your own site does not give you unrestricted file access to the Host. Connected Sites explains this distinction between use on the Guest site and access to the Host's files.

Your file and folder actions on the Host's files are recorded in both sites' History. Your site's record uses the _/Sites/<host-site-id>/... path, while the Host's record uses its own file or folder path. This also applies to actions through your site's Share Links and workflows.

The Host does not receive access to your site's files from this connection. Either site's Site Administrators can unlink the connection to remove access through it without deleting files on either site.