To install and upgrade Folder HelpDesk you need to have the following permissions:
The Folder HelpDesk network folder: Write permission
The Folder HelpDesk Outlook folder: Owner permission. You also need to be administrator over the client machine.
Think about this if you get problems:
You may be administrator over the local machine or over a domain and still only have read permissions over a network path.
The Outlook folder has its own permissions. It could be read, write or owner. Make sure that you are owner.