Import Data form Slack to Mattermost

1

Hey,

I followed this tutorial to import data from Slack to Mattermost:

https://docs.mattermost.com/onboard/migrate-from-slack.html#import-data-into-mattermost

I can perform almost all steps.

But when I run the last command

mmctl --local import job show <JOB ID> --json

I get this error:

[
  {
    "id": "exopj365tpbe5nnujfwm3n9hoc",
    "type": "import_process",
    "priority": 0,
    "create_at": 1732453692632,
    "start_at": 1732453706955,
    "last_activity_at": 1732453730968,
    "status": "error",
    "progress": -1,
    "data": {
      "error": "Error during job execution. — UpdateUserRoles: Cannot demote last System Admin.",
      "extract_content": "true",
      "import_file": "gqsw6xg3sprc789ps761dq7qxa_mattermost-bulk-import.zip",
      "line_number": "246",
      "local_mode": "false"
    }
  }
]

Unfortunately I could not find anything about it on the internet. Any Ideas?

Many thanks :slight_smile:

2

Hi @lemmi25, thanks for reaching out! The error indicates that the import process is attempting to demote the last System Admin in Mattermost, which isn’t allowed. To resolve this, ensure the imported data has at least one user set as a System Admin. You can review and adjust roles in your bulk import file before retrying. For more details, check out the Slack Migration Documentation. Let us know how it goes! :blush: