An OST file does not contain items that are not in the mailbox, so the user will not 'lose' items by deleting the old OST file. If an item is in the mailbox then it should be in the OST file. A new OST file should contain everything the old OST file contains. Creating a new OST file doesn't 'pick up where the last one left off'. Note that this will affect new OST files, not existing OST files, so you'll need to remove the existing OST files by toggling cached mode off and on, deleting the existing OST file in between.Īn OST file is a cached copy of the mailbox. You'll need the appropriate Office version ADM/ADMX files in order to do so.

You can set the default path for new OST file using Group Policy. The former would never happen, otherwise the user wouldn't be able to log on to the TS and therefore couldn't use Outlook in offline mode, and the latter almost never happens, unless the Exchange server is offsite. One of the reasons to use cached mode is so that the client can use Outlook while disconnected from the network or from the Exchange server. If you can avoid it, don't use cached mode on a Terminal Server. I am not quite sure if the new OST file will still have cached the emails which where available in the old ost, or will it start caching from where the other one left. Then I thought if it is possible to limit the size of the ost file? Or limit the time that it keeps emailed cached, say just emails from the last 6 months are sufficient.Īnother solutions that came to my mind, moving the ost files somewhere else, this required the old ost file to be removed, and creation of a new one. Is there a way to limit the size of the *.ost files? I read in forums that having the Outlook 2010 set up in Cached Exchange Mode isn't the best practice for an environment where the hdd space is a major constraint.įirst thing that came to my mind is using folder redirection, and place the ost files (together with the AppData forlder) in a network share, but this does not help, because the ost files are saved a part of the AppData folder which can not be redirected. The Outlook is installed on the Terminal Server and various users can use it. Our Terminal Server is running out of hard disk space, and the major files which occupy most of the space are *.ost files of the Outook, which come form the users which use the Terminal Server all the time through remote desktop.

Office 365 terminal server