Backupery for Slack produces a zip archive that may be uploaded back to Slack if necessary. The archive is placed into the ReadyToImport directory:
To import the archive into Slack you’ll need to use the Slack import tool. After successfully importing the data you may notice that the file uploads are not imported properly. Namely, if you try to download any of the files, you’ll get a wrong file.
The cause of the problem is that Slack requires the archive to have so-called “File Download Token” inside. The token is generated only if you run the export manually using Slack Export Tools:
Currently, it’s not possible to generate the token automatically on behalf of any third-party application.
However, we’re currently working on workarounds we can provide for you if you need to import the files. Please contact us and we’ll be happy to discuss all the possible ways to import the files.
Other options here are that your backup file is so large that when you share it with Slack via (say) Google Drive, the Google filescan fails (in the background) and your file upload fails with no useful error messaging from Slack.
In which case, you need to rebuild the share URL that you copy from Google Drive before pasting it into the relevant field during import, as follows:
https://drive.google.com/uc?export=download&confirm=t&id=
Hi Benjamin! Thanks so much for your comment. Definitely worth adding it to the FAQ. I’ll format this text and put it as a separate item.