Users receiving "access is denied" when saving attachments in adobe acrobat/reader

Hi,

We are having an issue where we redirect the user's temp location to the C drive under a specified folder (i.e. c:\redirtemp\%USERNAME%\) but as it is a terminal server, this location is not browsable. It is however, from a network share which is mapped as X.

So when I open an attachment in Outlook 2013 (pdf for example) but then go File > Save As it immediately tries to access the temp location which is cannot browse to, and so users are greeted with the usual "operation cancelled due to restrictions in effect" message.

I have tried changing the HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Security\OutlookSecureTempFolder to the network drive which should then be X:\%USERNAME%\Temp\Temporary Internet Files\Content.Outlook\

I still get the operation cancelled message and the attachment is still loaded from the temp location on the C drive.

It appears outlook is completely ignoring this registry key. Is there any known issue with doing this?