Folder redirection
There are several ways to redirect certain folders from within the user profile, including (but not limited to) the Start Menu, My Documents or Temp folders. This customization can be done directly on the computer or with network management software, such as Microsoft Active Directory and Group Policies. These types of customizations can cause failures in the AutoCAD secondary installer which might result in error messages, such as Error 1606: Unable to access network location. To correct this issue, you should remove folder redirection from the user, reboot the machine, and then try to run AutoCAD again.