locked
Outlook 2010, One Google IMAP account, Two PST files? RRS feed

  • Question

  • Hi all. I have read a number of threads on this subject but it seems rare that there's ever a "here's exactly how this all works" type of explanation.  I don't have roaming users, and my purpose here is to understand how to manage an environment that uses Outlook 2010 with Google's Gmail IMAP service. 

    I just put in a new Win 7 x64 machine for somebody, installed Outlook 2010 x64, and all Windows Updates were then done.  No account added yet. 

    I open Outlook and run through the process for manually adding a new account.  Since this is Google, IMAP/incoming mail is imap.gmail.com on port 993 using SSL, and outgoing mail "uses the same setting as my incoming server", and is sending to smtp.gmail.com on port 465 using SSL. 

    I finish up with those settings, and go into Outlook. 

    As thousands have posted before me, I now see two PST files if I go to Data Files. 

    The particulars are this:

    • one email account only, user@abc123.com (a domain name registered with Google to use Gmail on)
    • two PST files showing in the Data Files tab:  user@abc123.com (user@abc123.com.pst), and "Outlook Data File" (Outlook.pst), each in the default locations other have posted about (Documents/Outlook Files, and the AppData/Local location)
    • Under Email Accounts tab, the default location for new messages to arrive, go to user@abc123.com/Inbox .
    • Outlook Data File has the checkmark next to it indicating it is the default PST.  If I click on this data file, interestingly, I have the option to "Set as Default", even though it already is.  Normally this is greyed out if you highlight the PST that is already default. 
    • user@abc123.com is not the default PST, and highlighting this PST in the list does not give me the option to Set as Default (greyed out).  Also weird, then again when it comes to IMAP, I get the feeling these are not really "true" PST files, at least not the IMAP-specific one (user@abc123.com.pst)
    • When I sent a test message, it went from the Outbox of the Outlook Data File, NOT the IMAP PST (user@abc123.com), but if I check the contents of the Sent Mail folder within the [Gmail] folder (see below), it shows, as well as under Sent Items of the Outlook.pst file. 
    • Of course new messages incoming show up in the Inbox of the user@abc123.com PST file.
    • The contents of the user@abc123.com PST file are:  Inbox, [Gmail], Junk Email, and Search Folders.  The [Gmail] folder represents the IMAP folder structure of the google server with the same folder names you'd see if you logged into gmail.com, so that's all fine. 

    Keep in mind that all of this is completely default.  This is not a roaming user, and I have made no changes to any settings, other than to change the initial port #'s and such during account creation.  So this PST file behavior is what Outlook does as of May 9 2014 and I imagine that will not change.   

    Question is:  how can I manage these PST files?  If I had to replace this user's computer one day, do I copy both PST files, or just the Outlook Data File, since the IMAP one is presumably just an offline file representing the server copy?  Is there some sort of comprehensive Outlook-centric description of how IMAP stuff works and the expected PST file "best practices"?

    Thanks. 

    Saturday, May 10, 2014 2:01 AM

Answers

  • The reason for there being two .pst files in Outlook 2010 is basically that one (your IMAP mailbox .pst file) is as you say a local cache of your IMAP account, while the second (the Outlook.pst) stores everything else that doesn't get stored in your IMAP account on the server. Since things like calendar, contact and task items aren't supported by IMAP you need somewhere to store them, so you have a second .pst file.

    For backup purposes you definitely want to backup Outlook.pst file, since that contains the data which is only found locally, so re-setting up the IMAP account on another machine will not restore that data otherwise.

    For the IMAP .pst file, it may be worth backing it up as well just so you have a copy, but in the event of you needing to setup the mailbox on another machine / after a restore you cannot use that .pst file. The file is specific to the profile it's configured in, so while you can view the messages held in there (assuming you have Outlook configured to download the message content) it can't be re-attached to a IMAP account on another server, as mentioned here http://www.slipstick.com/outlook/config/how-to-move-the-imap-personal-folder-pst/#reuse

    You may have seen these already, but http://www.msoutlook.info/question/754 actually discusses how this is handled differently in 2013, but for background explains the 2010 situation well, and http://superuser.com/questions/206788/understanding-nuances-of-outlook-2010-with-imap-email also discusses the use of data files by IMAP accounts.

    Saturday, May 10, 2014 9:12 AM

All replies

  • The reason for there being two .pst files in Outlook 2010 is basically that one (your IMAP mailbox .pst file) is as you say a local cache of your IMAP account, while the second (the Outlook.pst) stores everything else that doesn't get stored in your IMAP account on the server. Since things like calendar, contact and task items aren't supported by IMAP you need somewhere to store them, so you have a second .pst file.

    For backup purposes you definitely want to backup Outlook.pst file, since that contains the data which is only found locally, so re-setting up the IMAP account on another machine will not restore that data otherwise.

    For the IMAP .pst file, it may be worth backing it up as well just so you have a copy, but in the event of you needing to setup the mailbox on another machine / after a restore you cannot use that .pst file. The file is specific to the profile it's configured in, so while you can view the messages held in there (assuming you have Outlook configured to download the message content) it can't be re-attached to a IMAP account on another server, as mentioned here http://www.slipstick.com/outlook/config/how-to-move-the-imap-personal-folder-pst/#reuse

    You may have seen these already, but http://www.msoutlook.info/question/754 actually discusses how this is handled differently in 2013, but for background explains the 2010 situation well, and http://superuser.com/questions/206788/understanding-nuances-of-outlook-2010-with-imap-email also discusses the use of data files by IMAP accounts.

    Saturday, May 10, 2014 9:12 AM
  • Hi,

    Just checking in to see if the information was helpful. Please let us know if you would like further assistance.

    Thanks,

    Melon Chen

    Forum Support


    Come back and mark the replies as answers if they help and unmark them if they provide no help.

    If you have any feedback on our support, please click here
    Tuesday, May 13, 2014 6:43 AM
  • Hi,

    I'm marking the reply as answer as there has been no update for a couple of days.

    If you come back to find it doesn't work for you, please reply to us and unmark the answer.Thanks,

    Melon Chen

    Forum Support


    Come back and mark the replies as answers if they help and unmark them if they provide no help.

    If you have any feedback on our support, please click here
    Friday, May 16, 2014 7:11 AM
  • Sorry I didn't notice the reply notification for this thread - thank you for the answers very much. MSFT forum support has already marked as answer else I would have but in either case your help is much appreciated.
    Wednesday, June 4, 2014 3:22 PM