You’ll find step-by-step instructions in the guide: Moving the ost-file of an Exchange, or IMAP account. This may sound all very complex, but the actual process is quite easy and very effective. This differs from a shortcut as a shortcut is actually an lnk-file whereas a Symbolic Link will retain the original file name.

With a Symbolic Link, you’d be creating a “pseudo file” which is only a pointer to the actual file. Instead, the quickest way to go would be to create Symbolic Links instead. Moving the ost-file in Outlook 2013 and later is no longer possible via the interface in Outlook itself. Move the ost-file for Outlook 2013 / 2016 / 2019 / 365 Exchange and IMAP accounts While it is recommended to leave the ost-file in its default location, there are still valid reasons for moving it to another location like for instance when using a smaller Solid-state Drive (SSD) as your main disk. Moving an ost-file to another location is indeed a bit more trickier than moving a pst-file. How can I move my ost-file to another location? I know how to move pst-files, but that method does not seem to apply to ost-files. I'm running out of disk space on my main drive and noticed that my ost-file was really big.

Move appdata to another drive