Beginning with Microsoft Outlook 2010, you can open more than one Exchange account in your Outlook profile.
So how many Exchange Accounts can you add to an Outlook 2010, Outlook 2013, 2106, or Outlook 2019 profile?
In Microsoft Outlook 2013 and newer, the default is 10 accounts and the maximum allowed is 9999 accounts. Outlook 2010 supports up to 15 accounts in your profiles, but, by default it is limited to 5 accounts.
If the administrator wants to allow more (or less) than the default number of accounts, he or she needs to edit the registry or apply a group policy.
The relevant Group Policy key for all supported versions of Outlook is:
HKEY_CURRENT_USER\Software\Policies\Microsoft\Exchange
DWORD: MaxNumExchange
Outlook 2010 values: a decimal value between 1 and 15
Outlook 2013 values: a decimal value between 1 and 9999
Outlook 2016 values: a decimal value between 1 and 9999
Outlook 2019 values: a decimal value between 1 and 9999
In the Group policy editor, the setting is under Outlook > Account Settings > Exchange > Set maximum number of accounts per profile.
If you prefer not to add it as a policy, use these keys instead. Note: if you are using the consumer or Business version of Outlook 2013 and newer, you may need to use these keys instead.
HKEY_CURRENT_USER\Software\Microsoft\Exchange
DWORD: MaxNumExchange
Outlook 2010 values: a decimal value between 1 and 15
Outlook 2013 values: a decimal value between 1 and 9999
Outlook 2016 values: a decimal value between 1 and 9999
Outlook 2019 values: a decimal value between 1 and 9999
The new setting won't take affect until you restart Outlook.
Do it for me
To set the registry key to allow 15 accounts, use this registry file. This works with Outlook 2010, 2013, 2016, or 2019. (In HKCU\Software\Microsoft\*)
15 Accounts, user keys
This registry file will set a Policy key to allow up to 15 Exchange accounts; works with Outlook 2010, 2013, 2016, or 2019.
(In HKCU\Software\Policies\*)
15 accounts
Ive added the key to the registry, but it would be pretty helpful to add to the article that one needs to right click, modify, choose decimal and enter value 1-9999 for number of accounts.
End result would be a key called MaxNumExchange \ REG_DWORD \ 0x0000270f (9999)
FYI
In the following article from MS in 2022, they DO say you can have multiple Exchange accounts open in Outlook, if you basically have full access to them. They list the versions, and it goes back to 2010.
https://learn.microsoft.com/en-us/outlook/troubleshoot/profiles-and-accounts/issues-that-occur-when-adding-multiple-exchange-accounts
quote:
"In Microsoft Outlook 2010, Outlook 2013, Outlook 2016, Outlook 2019 and Outlook for Microsoft 365, you can add multiple Microsoft Exchange accounts to the same profile if one of the following conditions is true: "
You can add multiple accounts to a profile if you have the username and password - that is what my article is about.
The article you linked to refers to shared mailboxes added as accounts. For example, your own mailbox has full access permission on a mailbox and you add the mailbox as an account, using a username and password. When you do this, some features will be buggy.
What is the length of the UNIQUE PASSWORD LIST for Outlook 2013?
Does this apply for Office 365 Outlook Application installed on Windows 10
Yes, it uses the Outlook 2016 keys. Default is 10 accounts.
Does this also work for non exchange email accounts ? If not is there another tutorial for non exchange email accounts
Thanks
You shouldn't need a key with pop and IMAP accounts - they should allow unlimited.
Did you hit a limit and if so, how many accounts are in your profile?
Hi Diane
Is there a way to increase the limit of non-exchange email accounts that we can add to outlook ? I am talking about increasing the limit of gmail and yahoo accounts that we can add on the outlook app
I have been searching a lot online but all I find is how to increase the limit for exchange accounts ..
Thanks
How many account are in your profile and did you receive a message that you can't add more? I don't recall a limit to the number of internet accounts in a profile.
It's not working. As simple as that. And I cannot find any entry named outlook in the group policy editor. I'm using outlook 365 on Windows 10 Pro.
You need the office admin templates to use the group policy editor. The registry files I have linked in the article will set the key for 15 - if you need more, you can open the registry editor and change the value.
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Exchange]
"MaxNumExchange"=dword:00000015
Hi, just for information:
Office 2016 professional plus
You have to go to HKEY_CURRENT_USER\ Software\ Microsoft\ Exchange and add DWORD32bit with MaxNumExchange and decimal 15 (15 for example).
It is described above and works perfect.
Thanks a lot!