How to increase resources mailbox size RRS feed

  • Question

  • Hello all,

    Here we have a meeting room mailbox (resource mailbox) is almost full. Is there anyway to increase the resource mailbox size? or any other ways to achieve\clean the mailbox content?

    Thanks a lot. 

    Tuesday, August 21, 2018 2:57 AM

All replies

  • Hi

    Read the article below:


    Search, Recover, Export Mailboxes, Contacts, Calendars, Tasks from Mailbox(EDBs) and Office 365. Migrate/Recover into On-Premises Exchange Server, Office 365 with Kernel

    Tuesday, August 21, 2018 6:19 AM
  • Outgoing message size limit:  This setting specifies the maximum size of a message (in MB) that can be sent out from a resource mailbox. Note that you cannot set a maximum outgoing message size larger than 50 MB.

    Incoming message size limit:  This setting specifies the maximum size of a message (in MB) that can be accepted by a resource mailbox. Messages larger than this will not be delivered to the resource mailbox. Note that you cannot set a maximum incoming message size larger than 50 MB.

    Tuesday, August 21, 2018 7:34 AM

    Search, Recover, Export Mailboxes, Folders, Email, Contacts, Calendars, Tasks, etc. from Offline Exchange Databases (EDBs), On-Premise Exchange Servers and Office 365. Migrate/Recover direct from any offline EDB into any On-Premises Exchange Server, even cross version i.e. 2003 → 2007 → 2010 →2013 → 2016 → Office 365 with Lucid8's DigiScope

    Tuesday, August 21, 2018 6:43 PM
  • You can increase the mailbox quotas as otherwise suggested.  To archive or delete the content you could create a retention policy.

    Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."
    Celebrating 20 years of providing Exchange peer support!

    Wednesday, August 22, 2018 6:49 AM
  • Hi Charles,

    To increase the size of mailbox, you can use the command below.

    Set-Mailbox -Identity <MailboxIdParameter> -ProhibitSendQuota xxGB -ProhibitSendReceiveQuota xxGB -IssueWarningQuota xxGB -UseDatabaseQuotaDefaults $false

    To delete content in the mailbox, you can assign a retention policy to the resource mailbox, log on with a user who is given full access permission to delete, or use the following command to delete.

    Search-Mailbox -Identity <MailboxIdParameter> -SearchQuery YourQuery –DeleteContent 

    Before using the command, the administrator has to be given Discovery Management role and Mailbox Import Export role. Refer to the following articles.

    Assign eDiscovery permissions in Exchange
    Mailbox Import Export role

    Please feel free to post your questions, and I am glad to provide further assistance.


    Dawn Zhou

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    Wednesday, August 22, 2018 8:35 AM
  • This response does not address the resource mailboxes as described in the OP.  Apparently DavSteveDoe did not read the question.  We must search elsewhere for answers.
    Monday, October 21, 2019 5:26 PM
  • I actually found an answer but I can't post links until I'm verified.  My research indicates that resource accounts cannot be modified individually and the total size is shared among those accounts in aggregate.
    Monday, October 21, 2019 5:44 PM