Outlook 2016 Changing Location of .OST file

My current default location for my OST file is C:\Users\...\*** Email address is removed for privacy ***

I have been trying to change the location to D:\Users\...\*** Email address is removed for privacy ***, but nothing I try seems to work.

In Outlook, I go to change the location of the data file, but it doesn't allow me to edit or change the file. I did however find this article: https://support.microsoft.com/en-us/kb/2752583 which told me to go an edit the registry to use ForceOSTPath and then put in the full path of the location in which I want to use for my OST. But that doesn't work. Doesn't change anything.

How can I change the location in which outlook points to the data file for my email? It is pulling the emails off of the exchange server, but caching them to my OST file on my local C drive, instead of my other local D drive

Question Info

Last updated July 21, 2018 Views 8,050 Applies to:


Thank you for posting on Microsoft Community.

You have mentioned in the description that you are using an Exchange Server Account however the OST you are referring to shows that it is Outlook.com account, so what is the type of email account you are using?

Have you used the FIXIT tool mentioned in the article you have quoted to fix the issue? If not, you may run the FIXIT tool and check if it helps.

Thank you.

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After setting the path in the Registry, you must remove and re-add your account to actually change the location. Setting the Registry value doesn't affect any existing accounts.

Additionally see: http://www.howto-outlook.com/howto/movingostpstoutlookcomimap.htm

Robert Sparnaaij [MVP-Outlook]

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Thanks for the info! So, if I move my Outlook file to that location and re-add the account will it need to re-cache all emails or could it just start up on that location?

Another idea I had looked at was using a symbolic link, but when I did that I would open up outlook and it would always just say 'Connecting...' and it would never connect to my email, but I could still see my cached emails. What would be the proper way to fix that?

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Thank you for answering, but with all due respect, I think there is some misunderstanding on your part.

I have my own domain so I use a host service (for ex bluehost.com not that it matters) and they are offering e-mail service obviously. When you set up the e-mail, Outlook gives the option to set up as POP3 or IMAP.
I used in the past POP3 in which case the data file created is indeed a PST file (and yes can be moved wherever).

However now I want to access my e-mail from two computers and of course I want it synchronized between them, so I chose this time to set the e-mail in Outlook as IMAP.
Now Outlook created automatically an OST folder in the default location and can not be moved.

So the original question posted by Adjit is valid and he is not confused as you imply.

I have exactly the same issue.

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I have the same question.  Specifically, I want my OST file to be saved in a folder in OneDrive so I can always have a backup - and use the information on multiple computers.

Any guidance on how to do this would be greatly appreciated.


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The use of an Outlook data file on a Network or cloud location is not supported and will lead to data file corruption.

It should be located on the local PC

Only an exchange mail account will fully sync on multiple devices.

An IMAP mail account will sync mail only

You cannot 'backup' an ost data file (Well you can, but you cannot use that data file)

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Assuming I understand you, correctly, I wouldn't do what you are attempting, even if it were possible. Every single email will increase your OST file, by a minute amount. However, since it is a single file, my understanding is that the entire OST file will upload, after every email. OneDrive will see it as a single, edited file that requires replacing.

Assuming that your OST file is, say, 10GB; after every email, your PC will upload a new 10GB file. Of course, the same issues apply to PST files, too.

As I say, I may be misunderstanding you, so I apologise if I have the wrong end of the stick.

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