In Exchange Server 2013 if you are moving mailbox using CSV file you may get the above error. To resolve the issue please follow the steps listed below.
Lets see how to troubleshoot.
Figure 1 : Export Data
In figure 1 although we have the Email Address column, however it has a space which is the problem. If you export with this file you will get the below error.
Figure 2 : Error
In the error it clearly says “EmailAddress” column is missing.
Figure 3 : CSV file with corrected information.
Although the step is documented in the below article. This blog is to address the issue directly and start the migration.
Stay tuned more to come on Migration
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