Error Code Description Details
1 missing external id The parameter use_external_id was true and the contact has no value for the external_id.
2 missing email The email address is required when use_external_id is set to false or when the contact is new.
3 invalid email The syntax of the email address is not correct.
4 duplicate external id The value of external_id already exists for another contact, either in the provided list or under the persisted contacts.
5 duplicate email The value of the email address already exists for another contact, either in the provided list or under the persisted contacts. If you want to update contacts and receive this error, check the list of submitted contacts for duplicates.
6 illegal standard field value: address The length must not exceed 255 characters.
7 illegal standard field value: city The length must not exceed 255 characters.
8 illegal standard field value: firstname The length must not exceed 255 characters.
9 illegal standard field value: fullname The length must not exceed 255 characters.
10 illegal standard field value: hnr The length must not exceed 255 characters.
11 illegal standard field value: lastname The length must not exceed 255 characters.
12 illegal standard field value: organization The length must not exceed 255 characters.
13 illegal standard field value: region The length must not exceed 255 characters.
14 illegal standard field value: state The length must not exceed 255 characters.
15 illegal standard field value: title The length must not exceed 255 characters.
16 illegal standard field value: zip The length must not exceed 255 characters.
17 illegal standard field value: birthday Allowed patterns: yyyy-mm-dd and yyyy-mm-dd hh:mm:ss
18 illegal standard field value: nameday Allowed patterns: yyyy-mm-dd and yyyy-mm-dd hh:mm:ss
19 illegal standard field value: gender Allowed values: m (male) and f (female)
20 illegal standard field value: locale The value must follow the pattern: xx_XX (example: de_DE)
21 no such custom field The name of the custom field is not declared in the account.
22 illegal custom field boolean value Allowed values: 0, 1, true and false
23 illegal custom field float value
24 illegal custom field double value
25 illegal custom field integer value
26 illegal custom field string value The length must not exceed 255 characters.
27 illegal custom field timestamp value Allowed patterns: yyyy-mm-dd and yyyy-mm-dd hh:mm:ss
28 illegal standard field value: country „The length must not exceed 255 characters."
29 illegal standard field value: salutation „The length must not exceed 255 characters."
30 illegal Maileon ID The given contact ID is not a number or cannot be found