If you see "Error creating sequencer," "Error adding accounts," or an account that can't be selected when connecting to a sequencer, here's how to resolve it.
Use the right credentials
In Settings → Sequencers, the Configure step for Instantly and Smartlead uses your sequencer login email + password — not an API key. (Workspace Name, API key, and Consent URL fields are optional.) A common cause of connection errors is entering the wrong login or having 2FA enabled on the sequencer account.
Already connected to another Maildoso account?
A sequencer login can normally be actively connected to only one Maildoso account at a time. If that same Smartlead or Instantly login is still connected to a different Maildoso account, connecting it here can fail with "Error creating sequencer." Disconnect it from the other account first, or contact us to clear the old connection. Full details: "Error creating sequencer" when connecting Smartlead or Instantly.
Google Workspace vs SMTP
Google Workspace mailboxes: connect via Settings → Sequencers, then Email accounts → Add to sequencer.
SMTP mailboxes: export to CSV (use the "Other" format if your tool isn't listed) and bulk-upload in the sequencer. See How do I upload emails to my cold email tool?
If your login is correct and it still fails, it's likely a backend error on our side — contact support and we'll fix it.