There was an issue with Telerik Handler used by RAD editor ( A third- party editor tool used by ACM). 

All self hosted customers need to prevent access to the telerik handler. The steps are given in detail here:

I have also attached this as a PDF. 


if you had it turned off so the major impact is that the pop ups don’t work. Let me show you some screenshot to help understand better.


So when you right click on the image, the above dropdown box shows up. Here these options open up dialog boxes as pop up (i.e. when you click properties, the properties pop-up appears) .

But because of this configuration being blocked, we now get an error :


The main workaround to get around this issue is to use HTML code to change the height and the width ( which is why the properties option is mainly used for) Or you could always use another Editor like Tiny MCE ( change it from My Page)