It seems that this is a known issue with our RadScheduler control and a css workaround posted in our Misalignment section located here
might avoid that unusual behavior
. Please take a look at the second common problem "In Browser Mode Compatibility IE9 the time slots of the RadScheduler twist to the left
" and the solution below the image. It is quite possible that the right click is not working because the time slots are twisted to the left and you are actually not clicking on a time slot.
the Telerik team
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