Outlook doesn't stay online-only

Honored Contributor

I have Office 2019 pro plus, my Outlook is version 2002 (insider)


I didn't want Outlook to download my emails and use local disk space




so I went here:




and unchecked the Cached Exchange Mode.

after I restart Outlook, I go there again and I see the box is checked




tried this few times and same thing happens every time.

any ideas?



7 Replies


Are you using an account? In that case, you can't disable Cached Mode.

Note that you can also adjust the amount of data which is being cached by using the Sync Slider. You can set it for instance to 1 month to reduce the data footprint of the ost-file.

Yes I'm using my personal MSA,
I had no idea I couldn't use it for accounts because it didn't show me any notice or warning.
Outlook program should grey out that option for free MSA because this causing confusion for users.

oh and I tried to use the slider, set it to 1 week, restarted Outlook and then when i go back I see it's set back to "All" again. tried this multiple times. not sure if it's a bug only on insider ring or it's universal.
I would appreciate if someone else could confirm this possible bug using Outlook 2019 and a free MSA.

lastly, could you please point me to the documentation where it says Cached mode isn't available to free MSA? thanks in advance


You can refer to this post made by Gabriel Bratton who works for Microsoft and is a Support PM for Outlook;

Disabling cached mode for 


I haven't verified what the minimum cache period is for but I expect it to be longer than 1 week. The default is 6 months for disks larger than 64GB.

following the guide in here:

Outlook 2019 version 2002 always downloads All of my emails, the slider reverts back to "All" after every Outlook restart
best response confirmed by HotCakeX (Honored Contributor)

I think I found the bug,

so apparently Only setting the slider to 1 month and older works and it won't revert back to "All" after Outlook restart.






which means anything less than 1 month (i.e 2 weeks, 1 week, 3 days etc) fails,







resulting in the slider to revert back to the default "All" value.

(if this is another limitation of free MSA, there is no warning or notice shown to the user)






This is from Outlook 2019 - Insider - Version 2002 - (Build 12513.20010 Click-to-Run)


I hope Outlook developers see this post and fix the bug, again it'd help if someone else could reproduce this bug using Free MSA on Outlook 2019 or Outlook 365.


Others improvements that need to be done:

  • Either grey out Or show a notice or warning to users that are logged into Outlook program with a free MSA (, etc) when trying to disable cached mode option, saying that it's not possible to disable cached mode when using a free MSA.


Yeah, 1 month minimum sounds about right. Thanks for the testing and confirming it.

I'll ask internally whether this can be properly published and be made clearer in the interface.

Sounds great, thank you very much!