This article lists the data types that ProBackup backs up for Slack and any known limitations.
What we back up
Users
Public channels
Private channels the connected user is a member of
Direct messages and group direct messages the connected user is part of
Messages
Threads (up to 1,000 messages per thread; see the limits below for workspaces connected since 29 May 2025)
Files and attachments shared in messages
What we don't back up
Direct messages between other users
Channels the connected user does not have access to
New backup updates for archived channels (messages saved before archiving remain subject to your backup retention period)
Group membership and permissions
Workflows
Note: ProBackup can only back up data that the connected user has access to. To ensure full coverage, consider connecting an account with broad channel access or inviting additional team members.
Message history limits for workspaces connected since 29 May 2025
Since 29 May 2025, Slack strictly limits how much message history apps outside the Slack Marketplace can read for new installations. For workspaces connected to ProBackup on or after that date:
The first backup includes the most recent messages of each conversation, not the full history.
Daily backups collect recent messages from conversations with recent activity. Coverage can be incomplete, particularly for thread replies or after a gap in successful backups.
Long threads may be backed up partially.
ProBackup does not apply this initial-history restriction to backups connected before 29 May 2025. Thread-length and access limits still apply.