If you searched “what is PersonMetadata in Outlook”, the short answer is that it is a hidden folder in your mailbox, not a contact setting you can open or edit. Most guides describe it as a list of contact fields and social profiles, and that is wrong. You only run into it when blank items with no subject show up in a Search Folder, or when you get a warning that the folder is close to its item limit. In this guide, I’ll show what the folder holds, why those blank items appear, and how to check or empty it.
Quick Answer: PersonMetadata is a hidden folder in your Exchange mailbox, not a contact feature you can open in Outlook. Microsoft says it was created for Outlook Customer Manager, a service deprecated in June 2020, but Outlook still uses it. You normally never see it, except as blank items in a Search Folder or as an item limit warning.
What Is PersonMetadata in Outlook, Really?
Microsoft documents the folder in one place, a troubleshooting article about Search Folders. It says the folder was created and used by Outlook Customer Manager (OCM). The OCM service was deprecated in June 2020, but Outlook still uses the folder. Whenever a new item is created in your Contacts folder or in the Recipient Cache folder (a hidden folder under Contacts), a related item is created in PersonMetadata.
So the folder follows your contacts and the people you email, and it grows as they do.
It stays out of sight because Exchange lets a folder be flagged as hidden, and Outlook then keeps it out of the folder pane (Microsoft describes this flag, PidTagAttributeHidden, in its documentation for hidden folders). Microsoft also says the folder and the items in it will be removed from the service in the future. It gives no date.
Where Your Contact Details Really Live
The name, job title and phone number you see for a colleague do not come from PersonMetadata. They come from your own Contacts folder and from the address book your company publishes (the Global Address List). In classic Outlook, you reach them with the Search People box in the ribbon or the People page in the side panel. The Address Book button next to To, Cc and Bcc opens the same lists, as Microsoft shows on its page to find people and contacts in classic Outlook.
In Outlook on the web, the People page does the same job.
If a colleague’s job title is wrong there, an admin fixes it in the directory, not in Outlook (I covered it in how to change a job title in Outlook). It is also a different thing from the hidden data you remove from Word or Excel files with File > Info > Check for Issues > Inspect Document.
Why Do Items With No Subject Show Up in My Outlook Search Folder?
If you created a Search Folder for all mail items and it lists items with an empty subject line, those are PersonMetadata items. Point to one and Outlook shows “In folder: PersonMetadata”. Microsoft’s article covers classic Outlook for Windows (Outlook 2013 to 2019 and Outlook for Microsoft 365).
To keep them out of that Search Folder:
- Right-click the Search Folder and click Customize This Search Folder.
- Click Browse and clear the Search Subfolders option.
- Select the folders you want to include yourself.
That is all. The items stay in the mailbox, they just stop appearing in your Search Folder.
What Happens When the PersonMetadata Folder Reaches the 1 Million Item Limit?
Exchange Online allows 1 million messages in one mailbox folder, and it sends a warning to the mailbox owner at 900,000. When a folder hits the limit, new messages can’t be delivered or saved in it (see the Exchange Online limits). If you want the full picture of mailbox limits, my post on how to see your Outlook mailbox size covers it.
Microsoft says that if you get a folder item limit notification saying PersonMetadata is approaching the 1 million item limit, you should delete all the items in that folder. Before that, check how many items it holds. An Exchange Online admin can do it with PowerShell, because the folder statistics cmdlets count hidden items too (see Get-EXOMailboxFolderStatistics):
Connect-ExchangeOnline
Get-EXOMailboxFolderStatistics -Identity user@contoso.com | Where-Object {$_.Name -like "PersonMetadata*"} | Format-Table Name,ItemsInFolder,FolderSizeReplace user@contoso.com with the mailbox address. If the count is nowhere near 900,000, leave the folder alone.
Can You Delete the PersonMetadata Folder?
Microsoft only documents emptying it, and only when you get the folder item limit notification. It gives no steps to delete the folder itself, so don’t try. There are two documented ways to empty it.
Method 1: MFCMAPI, for a few users. MFCMAPI is a free tool that Microsoft links to from the article. Make sure Outlook is closed first.
- Start MfcMapi.exe and click OK.
- Click Tools > Options, tick Use the MDB_Online flag when calling OpenMsgStore and Use the MAPI_NO_CACHE flag when calling OpenEntry, then click OK.
- Click Session > Logon and select the profile for the mailbox.
- Double-click the Microsoft Exchange Message Store that has Default Store = True.
- Expand Root Container > Top of Information Store and click PersonMetadata. (The text for Top of Information Store can be in another language, depending on the mailbox regional settings.)
- Right-click PersonMetadata > Advanced > Empty items and subfolders from folder.
- In the Delete Items and Subfolders box, select Hard Deletion and click OK.
MFCMAPI can look frozen for a long time while it deletes. Microsoft says to watch the progress with Get-MailboxFolderStatistics.
Method 2: the EWS script, for many users. An admin runs Microsoft’s CleanPersonMetadata.ps1 script with a service account that has impersonation set up, for example .\CleanPersonMetadata.ps1 -Identity user@contoso.com. Add -WhatIf first to simulate it. Both methods hard delete, so the items do not go to Deleted Items. The setup steps are in the Microsoft article, and they need the EWS Managed API and the Exchange Online PowerShell module (ExchangeOnlineManagement).
Does This Apply to New Outlook, Outlook on the Web and Mac?
Microsoft’s article is written for classic Outlook for Windows. It does not mention new Outlook for Windows, Outlook on the web, Outlook for Mac or the mobile apps. The folder lives in the mailbox on Exchange, so the PowerShell count above does not depend on the client. MFCMAPI is different: it logs on with a Windows Outlook profile, so use a PC that has one for that mailbox. Not sure which Outlook you have? See how to know if you have new Outlook or classic Outlook.
When one user only sees blank items in a Search Folder, change the Search Folder and leave PersonMetadata alone. If you manage the mailboxes, run the count for your heaviest users before the 900,000 warning arrives, since the folder gets new items with every new contact and recipient cache entry. For folder limits in general, see how many folders you can have in Outlook.
