>>Your stack trace shows a call to CopyToDataTable, but nothing in the code you posted appears to be calling th
>
>Tell me you don't really read stack traces for errors, do you? <g>

It was funny because it looked to me that the error was on the foreach line (at least I think it was - I probably pressed green button to continue without realizing it). I did a minor change in the code by using ToList() first and then the rest of the code. This time I found that it was indeed CopyToDataTable() line and also this is the relevant Connect issue

https://connect.microsoft.com/VisualStudio/feedback/details/422727/major-flaw-in-system-data-datatableextensions-copytodatatable-design