Hi Kiat,
Generally, the installer requires the admin privilege to run so in that case it ensures the privilege to download the files to any directory selected.
We are thinking of improving the installer so we are hoping you can help us reproduce this issue locally to make sure the change we make can fix this properly and to also verify the fix locally. Can you provide some information like how are the privilege of this folder is delegated? Why didn't it have sufficient privilege to download files to this folder even though you already ran it as admin?
If these questions are not related to the cause of the issue, please advise otherwise. Thanks in advance!
Yes, "being an administrator" and "running as administrator" are different as an administrator user has two set of privileges (full admin privilege and reduced privileges). But the installer is designed to require admin privileges to run. When you simply double-click the installer to run and it detects it's not using admin privileges, it pops up a UAC window for elevated privileges. So either way, the install ensures the full admin privilege.