Box as the Custom Files Store in Slack enables you to use Box to securely store all files uploaded in your Slack conversations. Box as the Custom Files Store in Slack is also available on mobile devices, so you can share content even on-the-go.
Custom Files Store is the term Slack uses to indicate files shared in Slack channels and conversations are stored in Box.
By enabling the Custom Files Store feature:
- Uploaded local files go directly to Box through the Slack interface without passing through Slack servers.
- Uploaded content resides in a Box folder associated with a given Slack private channel, public channel, or direct message conversations (chats).
See also the API documentation.
Custom Files Store is best suited for customers who use Box within a specific Slack workspace or organization. Users without Box accounts will not be able to upload content, including screenshots or images, into Slack.
Mapping of Slack channels to Box folders
As soon as a user uploads a file into a Slack channel, Box for Slack creates a folder associated with this channel, and adds a Slack bookmark called Channel files. The folder is named the same as its associated channel. The parent folder is associated with the channel’s Slack Workspace, and the root folder is named Slack Channel files. Additionally, Workspace and channel sharing folders define the mapping structure, each following the first character of the name. For example:
- All Files
- Slack Channel Files
- Workspace X
- Channel B
- Channel C
- Channel B
- Workspace X
- Slack Channel Files
The Box admin can also map a Slack channel to an existing Box folder outside this default structure. To designate an existing Box folder as an upload destination for a specific Slack channel, see these articles. Prior to mapping a Box folder to a Slack channel, the Box admin must set the Box for Slack service account as the folder’s co-owner or owner. The folder mapping can be changed anytime, and before or after an upload happens in the channel.
Mapping a custom Box folder is available only for regular Slack channels, and is not available for Conversations or Slack Connect channels.
Mapping between Slack channels and Box folders also applies to users: channel members who have authorized the Box for Slack app become editing collaborators of the associated Box folder.
This mapping is maintained up-to-date by the Box for Slack app. Changes in Slack reflected in Box include:
- Added and removed channel members.
- Channels moved to a different Workspace, renamed or deleted.
- Uploaded files deleted in Slack.
Slack message and file retention policies are not automatically applied to the content stored in Box. We recommend setting a Box retention policy for Slack folders independently.
For large channels (1000 or more members), the most common purpose of file sharing is to broadcast information rather than to invite to collaborate on editing its contents. Therefore, the folder for channels of 1000 or more members have a generated Shared Link in People in your company can view scope instead of channel members set as editing collaborators.
For a manually mapped folder, Box does not automatically sync the folder’s name with the Slack channel’s name, and the Box admin chooses one of two modes for managing access:
- Automatic adjustments to access. Box applies these automatic adjustments as either collaboration invitations or as shared links with People in your company can view scope, as described above.
- Non-automatic access adjustments, where the Box admin must ensure proper user permissions for the Box upload folders.
For direct message conversations (chats), the upload folders will be created in the Slack Conversation Files root folder, inside the personal folder of the user who was the first uploader in the given conversation.
- Slack Channel Files,
Slack Conversation Files,
John Smith - Slack Files,
- Kevin Marek, John Smith
- John Smith - Slack Files,
- User ...001
- User ...001 is an example subfolder for all enterprise users whose Box user ID ends with ‘001’ digits,
- XYZ is an example Slack Workspace name.
Folders within the Slack Conversation Files parent folder will also contain uploaded content in the following cases:
- Multi-party direct messages (group chats),
- Slack Connect channels,
- Large channels (1000 or more members) if People in the company shared links are disabled or enforced to auto-expire.
- Your organization must have a Slack-assigned CSM.
- Your organization must be a paid Box business account with access to the Box admin console.
Recommended settings when using Custom File Store with Box
- Shared Links should be enabled for folders.
- People in your company should be allowed to access Shared Links. (People in your company can view/edit should be an available option, when creating shared links)
- Shared Links auto-expiration should not be enforced.
- An organization-wide installation of Box for Slack is recommended if your organization has channels belonging to multiple workspaces at the same time.
- Users belonging to different segments should not be allowed to join the same channels in Slack.
Deploying Box as the content layer in Slack
Deploying Box as the content layer in Slack is a three-part process in the Admin Console, followed by a manual enablement required by Slack:
- Entering the Slack Organization or Workspace ID or IDs in the Box for Slack app configuration.
- Authorizing the Box for Slack app to use Box as Slack file storage.
- Ensuring the latest version of Box for Slack is installed in your Slack Organizations or Workspaces.
Ensure that the Box for Slack app is installed in the relevant Slack Organizations or Workspaces. (Note: the "Box File Picker" and "Share to Slack in Box" are separate integrations not relevant to the Custom Files Store enhancement.)
To enter the Slack Organization ID in the Box for Slack integration
- Log into the Box Admin Console as a Box Admin.
- Go to Apps > Box Apps & Integrations.
- Scroll down to the Individual Application Control section.
- Search for Box for Slack.
- On the right-hand side, click Configure.
- Scroll down to the Box content layer settings, then enter the relevant Slack Organization IDs or Workspaces in the Restrict to specific Slack Enterprise Grid Org ID allowlist / Slack Workspaces allowlist text fields.
Slack Enterprise Grid customers need to provide their Organization ID. If you are not a Slack Enterprise Grid customer, provide the Workspace ID.
To authorize the Box for Slack app to use Box as Slack file storage
- Go to Apps > Custom Apps Manager.
- Click Add App.
- In the Client ID field, enter:
- Click Next.
- Review the information, then click Authorize.
- You should now see Box as File Storage for Slack in the Apps list
To ensure the latest version of Box for Slack is installed in your Slack Organizations or Workspaces:
Install the latest version by following this link.
To fully complete deployment of this feature, there is a manual enablement step required by Slack. Contact your Slack CSM to complete enablement.
Removing Box as the content layer in Slack
- Contact your Slack-assigned CSM to request Custom File Store deactivation for your specific Slack organization IDs or Workspaces.
- Optionally, remove the Slack Organization IDs or Workspaces in the Restrict to specific Slack Enterprise Grid Org ID allowlist / Slack Workspaces allowlist text fields.
- Optionally, disable the Box as File Storage for Slack app in the Custom Apps Manager list.