Shared Mailbox cache behavior in Outlook

[Bruce Larson]

Has anyone seen issues with O365 Shared Mailboxes failing to update?

We have several, but one that has 500+ subfolders is very erratic for most users. They have to manually update and folders / emails are missing.

Unfortunately the SMB shares the .ost cache file with the user's mailbox so it gets very latge and hard to manage.

Tried recreating and repairing the cache with no luck.

Makes it tough to convince user that shared mailboxes are useful for them...

[#2 · Accepted solution]

Large OSTs or excessive number of folders are no-go, best use OWA in such cases. Or create a separate Outlook profile with just the shared mailbox.

[#3]

Unfortunately you can't have two different Outlook profiles running at the same time so not very useful. It does create a separate .ost though (which is the way it should work).
Thanks

[#4]

We use the policy of turning off the Download Shared Folders check box.  This forces the users to access any mailbox besides their own directly from the server copy.  It causes a slight delay opening, but we no longer receive the constant help desk calls about mailboxes not showing all messages.  It also helped with all the replication issues for admin/manager calendar updates.

[#5]

If you add a new account for the shared mailbox within the user's existing Outlook profile, it will create a separate (or  multiple if using the slider) OST file that is a lot easier to manage.

Also allows you to manage delegation, OOF, rules etc without needing to exit Outlook and use a separate profile.

Jonny