Attribute created failed with error: LanguageId should not be null

[ossie7]

When creating a new auto-number attribute on a custom entity I get the following error message:

Save attribute failed: System.ServiceModel.FaultException‘1[Microsoft.Xrm.Sdk.OrganizationServiceFault]: Languageld should not be null. (Fault Detail is equal to Exception details: ErrorCode: 0x80040203 Message: Languageld should not be null. TimeStamp: 2019-10-1ST08201:20.6321913Z Exception details: ErrorCode: 0x80040203 Message: Languageld should not be null. TimeStamp: 2019-10-15T08:01:20.6321913Z Exception details: ErrorCode: 0x80040216 Message: System.ArgumentNullException: Value cannot be null. Parameter name: Languageld should not be null. TimeStamp: 2019-10-15T08:01:20.6321913Z ).

The base language and user language is both set to Dutch (LCID 1043). No other language packs are enabled in this org.

[rappen]

Crazy late response....

What happens if you just enter 1043 in the "Language Id" field?