Unfortunately, the provided information is not sufficient for us to determine what exactly the reason for this problem is. Could you, please, open a support ticket and send us some additional information:
- Screenshots of both Image Managers - working and not working.
- The source of the Image Managers - right click on the manager\View Source .
- Please, send us your custom CSS styles.
In general, when you open the image manager you open a stand alone dialog which has his own styles. Most probably your custom CSS styles has nothing in common with the problem.
Looking forward to hearing from you.
the Telerik team