Hi,
I suppose type of Datacolumn is object if use ReadRange ativity…
Anyway, we cannot change type of DataColumn if data already exists.
The following sample is for create new datatable which has same name columns and expected data type.
Sample20211027-1.zip (8.9 KB)
If your datatable is very large, it might be better to write the above in InvokeCode.
Regards,