Most programs won't install correctly without such.
As to the 1606 Error, see the link below for various fixes to that issue:
Hope this helps.
When trying to install a program I am greeted with a message: "Internal Error: failed to expand shell folder constant userappdata".
I am not on an admin account but since it requires to be run as administrator, this is not an issue. A similar error occurs when I try to install another application "Error 1606: Could not access network location %APP DATA%".
It's apparent that both problems have to do with my AppData folder. However, all permissions are set properly. The folder is in its proper place and everything appears fine. I have cleared temporary files from IE, but the problem still persists. I have deleted the User Shell key in the registry and restarted, but still the problem persists.
I am frustrated and just want to find a way to fix this problem. Oddly when I searched the internet for a solution many people have been having the same exact problem. The even stranger part is that I have only found entries of this problem within the last two weeks. I don't know if this is a virus pandemic or something less sinister. All I want is a definitive answer on how to fix this issue. Every response I have seen thus far has done nothing to alleviate the problem. Read this entire message carefully and then come up with a response.