[Solved] Problem migrating from Slack, prerequisites

I’m following the instructions here Migration guide — Mattermost documentation to import Slack history into newly created Mattermost (set up with docker). The import fails, when I check the status with mmctl import job show <jobid> --json I get

[
  {
    "id": "...",
    "type": "import_process",
    "priority": 0,
    ...
    "status": "error",
    "progress": -1,
    "data": {
      "error": "Error during job execution. — BulkImport: Error importing channel. Team with name  \"<teamname>\" could not be found., resource: Team id: name=teamname",
      "import_file": "..._mattermost-bulk-import.zip",
      "line_number": "2"
    }
  }
]

I know the team name is the same as the Slack workspace and that the team exists on mattermost. What could be going wrong? I’m also wondering if the users need to be set up in Mattermost before migrating? The docs say “make sure that all users in Mattermost have the same username as in Slack, otherwise the import will fail”, I’m not sure how to interpret that.

My bad, silly: the team name did not exist on mattermost because it should be in lower case. (I assumed it would be the one I entered when creating the team via the UI which started with capital letter)

Heya edsav! Welcome to the Mattermost community forums, and I’m glad to hear you were able to identify and resolve the issue with the team name.

If you have any more questions or need further assistance, please don’t hesitate to follow-up!