Even if you see in the rlinq file that all key-generator nodes are set to autoinc, it is possible that some classes in the model do not have the key-generator option set at all. As the default key generator is HighLow (the one which requires the voa_keygen table), you would get the same error if you have any classes in the model with no identity properties or with identity mechanism set to Default.
For example, if you have classes mapped to views, they would not get automatically any primary keys and you would have to specify them manually. Please have a look at this article
for more details how to achieve this.
All the best,
the Telerik team
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