User mailbox is full 99%

Question

Hello experts,

We have one of our user where Mailbox data is 99% full and this mailbox archive is enabled with Auto expand feature which is occupied with 50%

This mailbox is placed on eDiscovery Hold so that user is unable to remove mails from Deleted folder which is occupied nearly 70GB and I checked few forums and they are suggesting to delete this mailbox from Hold and delete the deleted items folder and enable Hold again but this process our Legal team will lose data

Can someone suggest any other possible way to reduce the mailbox quota for this user

I tried Personal archive 6 months option it's also not working as it's on Hold.

Please suggest.

Answer 1

Hi, @Mani

Based on your description, I understand that your mailbox is almost full and on eDiscovery hold. I will begin with the following clarification:

When a mailbox is placed on eDiscovery (or Litigation) Hold, each item (even if the user deletes it) remains in the Recoverable Items folder. In essence, any deletion or cleanup you perform from the front-end (such as emptying the Deleted Items folder) will not free up space because a copy of the item is automatically retained for compliance purposes. This means that retained items cannot be permanently deleted without deleting (or modifying) them, which is of course unacceptable when legal requirements call for data retention. Unfortunately, this also means that any regular cleanup methods (users emptying deleted messages, or even applying retention policies via the Personal Archive setting) will not really free up space in the main mailbox, as the items continue to exist in the hidden area.

Suggestions in other forums to delete holds, clear the data, and then re-enable holds work only because the holds are deleted briefly. If your legal team relies on the complete capture of historical data, then this approach is unacceptable.

For this reason, you may want to consider the following factors:

1.Choose another Exchange Online license as required, which will increase the mailbox quota. Accordingly, this will increase costs and expenses.

2.You may consider performing an in-place archive export of historical data (using Compliance Search and Export PST). The exported PST can be stored securely (after legal review) and then you can remove some items from the active mailbox.

In summary, due to the nature of eDiscovery/Litigation Hold, there is no supported method of permanently deleting items while maintaining hold (thereby reducing mailbox size). Data is intentionally “protected” from deletion to comply with legal requirements. The only ways to reduce size include accepting a change in retention methodology (as approved by law) or meeting increased storage requirements through automatic archive expansion or other additional storage options.

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