<div>
Hello,<br />
<br />
The best practice in your case is to use a specific tool for your scenario. IdFix tool will help you to proceed and change duplicate attributes as UPN.<br />
<br />
You can find this tool here : <a href="https://www.microsoft.com/en-us/download/details.aspx?id=36832" rel="ugc">https://www.microsoft.com/en-us/download/details.aspx?id=36832</a>.<br />
<br />
Let me know !
</div>


Hello,

The best practice in your case is to use a specific tool for your scenario. IdFix tool will help you to proceed and change duplicate attributes as UPN.

You can find this tool here : https://www.microsoft.com/en-us/download/details.aspx?id=36832 [https://www.microsoft.com/en-us/download/details.aspx?id=36832].

Let me know !

<div>
Thanks. <br />
<br />
Do you know the answer of my questions?
</div>


Thanks.

Do you know the answer of my questions?

<div>
<div class="content wysiwyg-content">
In effort to migrate our Exchange 2010 users to O365, we have discovered we have a lot of users with duplicated UPNs. &nbsp;<br />
<br />
For ex, in the attached, the user login using adlopez but her User Logon Name in AD is &quot;alopez&quot;. &nbsp;There is also another users with that User Logon Name. &nbsp;<br />
<br />
2 questions:<br />
<br />
1. Can I just rename and enter adlopez in the User Logon Name field without causing any issue?<br />
2. Is User Logon Name is the same as UPN?<br />
<br />
Thanks.<br />
<a href="https://filedb.experts-exchange.com/incoming/2016/08_w36/1114494/adlopez.png" target="_blank" class="file-inline" title="adlopez (11 KB)"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><path d="M67.508 468.467c-58.005-58.013-58.016-151.92 0-209.943l225.011-225.04c44.643-44.645 117.279-44.645 161.92 0 44.743 44.749 44.753 117.186 0 161.944l-189.465 189.49c-31.41 31.413-82.518 31.412-113.926.001-31.479-31.482-31.49-82.453 0-113.944L311.51 110.491c4.687-4.687 12.286-4.687 16.972 0l16.967 16.971c4.685 4.686 4.685 12.283 0 16.969L184.983 304.917c-12.724 12.724-12.73 33.328 0 46.058 12.696 12.697 33.356 12.699 46.054-.001l189.465-189.489c25.987-25.989 25.994-68.06.001-94.056-25.931-25.934-68.119-25.932-94.049 0l-225.01 225.039c-39.249 39.252-39.258 102.795-.001 142.057 39.285 39.29 102.885 39.287 142.162-.028A739446.174 739446.174 0 0 1 439.497 238.49c4.686-4.687 12.282-4.684 16.969.004l16.967 16.971c4.685 4.686 4.689 12.279.004 16.965a755654.128 755654.128 0 0 0-195.881 195.996c-58.034 58.092-152.004 58.093-210.048.041z"/></svg>adlopez.png</a>
</div>
</div>


adlopez.png

In effort to migrate our Exchange 2010 users to O365, we have discovered we have a lot of users with duplicated UPNs.  

For ex, in the attached, the user login using adlopez but her User Logon Name in AD is "alopez".  There is also another users with that User Logon Name.  

2 questions:

1. Can I just rename and enter adlopez in the User Logon Name field without causing any issue?
2. Is User Logon Name is the same as UPN?

Thanks.

UPN issue.

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.

Exchange

Office 365 is a group of software plus services subscriptions that provides productivity software and related services to its subscribers. Office 365 allows the use of Microsoft Office apps on Windows and OS X, provides storage space on Microsoft's cloud storage service OneDrive, and grants 60 Skype minutes per month. Office 365 includes e-mail and social networking services through hosted versions of Exchange Server, Skype for Business Server, SharePoint and Office Online, integration with Yammer, as well as access to the Office software. All of Office 365's components can be managed and configured through an online portal; users can be added manually, imported from a CSV file, or Office 365 can be set up for single sign-on with a local Active Directory using Active Directory Federation Services.