O365 Exchange online archive and retention policy

It can take up to 30 days:

https://techcommunity.microsoft.com/blog/exchange/office-365-auto-expanding-archives-faq/607784

Hi @Nandan NK

Thank you for posting your question in Microsoft Q&A. 

We understand that your retention policy is not working as expected. This issue may be caused by a misconfiguration during setup. 

You could follow steps by steps to troubleshoot it: 

Verify the Retention Policy is Applied Correctly: 

Run:

Get-Mailbox "[******@domain.com](mailto:******@domain.com"mailto:******@domain.com")" | Select RetentionPolicy  

Ensure it matches your intended policy (e.g., the one with a 30-day "Move to Archive" tag as default for the whole mailbox). 

If not applied, assign it:

Set-Mailbox "[******@domain.com](mailto:******@domain.com"mailto:******@domain.com")" -RetentionPolicy "YourPolicyName". 

Check policy details:

Get-RetentionPolicy "YourPolicyName" | Select *.  

Confirm it includes a tag with RetentionAction: MoveToArchive and AgeLimitForRetention: 30.00:00:00 (for 30 days). 

Check and Disable Any Holds: 

Run:

Get-Mailbox "[******@domain.com](mailto:******@domain.com"mailto:******@domain.com")" | Select 

Look for RetentionHoldEnabled: True, LitigationHoldEnabled: True, InPlaceHolds, or DelayHoldApplied: True. If any are enabled, they block archiving. 

Disable retention hold:

Set-Mailbox "[******@domain.com](mailto:******@domain.com"mailto:******@domain.com")" -RetentionHoldEnabled $false. 

For litigation or delay holds, disable if not needed:

Set-Mailbox "[******@domain.com]" -LitigationHoldEnabled $false (but consult legal/compliance first). 

Check all mailboxes for holds:

Get-Mailbox -ResultSize Unlimited | Where-Object {$_.RetentionHoldEnabled -eq $true} | Select Name, RetentionPolicy, RetentionHoldEnabled. 

For eDiscovery holds, use the Microsoft Purview compliance portal to review and remove cases affecting the mailbox. 

Check for User-Applied Personal Retention Tags: 

Run:

Get-MailboxFolderStatistics -Identity "[******@domain.com](mailto:******@domain.com"mailto:******@domain.com")" | Where {$_.ArchivePolicy} | Select Identity, ArchivePolicy, FolderSize, ItemsInFolder  

This shows if personal tags are overriding the policy on specific folders. If found, instruct the user to remove them via Outlook (right-click folder > Properties > Policy tab). 

Force the Managed Folder Assistant and Monitor Progress: 

Run:

Start-ManagedFolderAssistant -Identity "

Wait 24-48 hours, as changes aren't immediate for large mailboxes. 

Monitor sizes:

Get-MailboxStatistics "

For ongoing monitoring, use this loop in PowerShell:

do {
    $Primary = Get-EXOMailboxStatistics -Identity "******@domain.com"
    $Archive = Get-EXOMailboxStatistics -Identity "******@domain.com" -Archive
    [PSCustomObject]@{
        PrimarySize = $Primary.TotalItemSize
        ArchiveSize = $Archive.TotalItemSize
        PrimaryItems = $Primary.ItemCount
        ArchiveItems = $Archive.ItemCount
    }
    Start-Sleep -Seconds 120  # Check every 2 minutes
} while ($true)

Look for gradual increases in archive item count/size. 

Verify Old Items Exist and Qualify: 

Run:

Get-MailboxFolderStatistics -Identity "

Confirm there are items older than 30 days based on received date (the policy uses this, not creation date). 

I'm looking forward to your response. Any update would be appreciated. I'm here to help.

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