Here you will find a list of the API error codes:
| Error code | Meaning |
| 1 | invalid API Key |
| 5 | need session before usage |
| 10 | permission denied |
| 20 | data not found |
| 30 | email invalid |
| 40 | email blacklisted |
| 50 | duplicate data |
| 60 | subscriber allready active |
| 70 | inserting order failed |
| 80 | batch to big (max 50) |
| 90 | subscriber allready inactive |
| 100 | given email is to short |
| 110 | no forms available |
| 120 | Error saving filter |
| 210 | Import is already running |