How to fix sync problems on large Outlook mailboxes
Excessive mailbox size, high item counts, and deep folder structures cause Outlook to fail to synchronize properly because users treat mailboxes like filing cabinets. While switching shared mailboxes to online-only mode can resolve these sync failures, large mailboxes continue to suffer from severe performance bottlenecks.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
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- 1Setting shared mailboxes to online mode onlyDid this help you?
- 2Caching less offline data such as 3 months instead of 1 yearDid this help you?
- 3Using Outlook webmail or the new clientDid this help you?
- 4Moving items to archives or SharePointDid this help you?
- 5Rebuilding the .ost fileDid this help you?
- 6Updating to the latest version of OfficeDid this help you?
- 7Ensuring advanced logging is disabledDid this help you?
- 8Running outlook.exe /cleanviewsDid this help you?
- 9Switching to the new OutlookDid this help you?
- 10Viewing the mailbox in OWA and permanently deleting the problematic syncing itemDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I have recently been working with a client getting a ton of these Synchronization Log emails in their Deleted folder in Outlook.”source ↗
“Well I just had another client put in a ticket for the exact same thing.”source ↗
“For a shared mailbox, we have set it to online mode only which has resolved our sync issue. The problem as you know is that people still use it as a filing cabinet.”source ↗
“Since a while we are experiencing synchronisation problems on mailboxen. These mailboxes are quite large. What are the criteria to avoid sync problems?”source ↗
Where this came up
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