I came across this recently. New pop-ups come up blank. Registering the typical IE related dlls will do the trick. I only had to register mshtml.dll. I used the command "regsvr32 mshtml.dll /s" without the quotes. I added that line to the logon script. If you dont use the /s script it will beep and prompt a window (not good for users or the help desk) Also a "sfc /scannow" could also be useful. Remember the inetcpl.cpl command as it is always overlooked.
Ryan
Systems Administrator