I recently ran into this very issue...
system: QC8116 (Dahau private branded)
Computer: Win7, IE11
Put your system into compatability mode. Put it into trusted sites. But there is ONE MORE thing that must be done:
Grant the login user "Backup File" permissions on the NVR. I went thru every single ONE of those undocumented perms to find out what dDMSS wanted. While at it? Don't log into the system remotely as "admin" - this is just plain dangerous on the net (unless you really want a net user formatting your HD).