Company users reflected a problem that they got stuck or hung up on the page while they tried to use Send To function of document in SharePoint, the processing window kept running after they have set up destination, sometimes it does not allow to close the windows.
So I started to test on my machine, and I got same situation in IE browser, then I tried to use this function through FireFox, I received different message 'Could not find the destination item or folder on this server.' First thought came to my mind is security issues, so I done a search of this problem, then I found relevant articles talked about ActiveX control objects to activate this function.
After I adjusted ActiveX objects of security settings in IE, then I received same error message as FireFox, but I still can't make it works even I enable all settings related to ActiveX objects.
Finally, it works after I adjusted security level to Low in Local intranet zone, after that I even tried to compare settings between Medium-low and Low, and tried to change settings one-by-one in Medium-low level to be the same as Low, but still failed.
You can set up Group Policy to help you deploy this settings in company users' machine to reduce working load, after you deploy this setting in group policy, you will find users' security level still remain the same, in fact, if you take look inside the settings, they are already changed.
For FireFox, I couldn't find the way to make it works, welcome to share any ideas or thoughts.