I have issues with the DhtmlxGrid on IE8/9, when a row is selected, it seems impossible to destroy the grid (while others browsers have no problem).
We have no JS errors in console, but when following execution, we can see on IE only we call the destructor. I tried to call myGrid.clearSelection() but the problem remains.
Unfortunately the issue cannot be reproduced locally.
If the problem still occurs for you, please, provide with any kind of a sample of your code or with a complete demo/demo link, where the problem can be reconstructed.