It seems that you are using rather old version of our controls - could you upgrade to a later one? The misbehavior you described was a known issue back then when IE was running in some compatibility modes.
Alternatively, please apply the CSS fixes from the RadScheduler troubleshooting section
. The point of interest is named - "In Browser Mode Compatibility IE9 the time slots of the RadScheduler twist to the left."
The other way around is to add a meta tag to your page
in order to force IE to render like IE8 or IE9.
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