unsupported version of Adobe InDesign

Dear SDL expert,

a client sent us 5 .idml files to translate. We were able to process 3 of them with SDL Professional 2017. For 2 of them, we keep on receiving the following error message: 'The selected IDML file was created by an unsupported version of Adobe InDesign

(Origin ISML v 1.0.0.0)

Could you help us at short notice? 

Many thanks, 

Michel