One or both of the following issues are encountered when using the Azure migration pipeline:
Migrating content from a SharePoint On-Premise environment to SharePoint Online (SPO) requires mapping the source user account to the target user account. For additional information about user mapping, please click here. However, the CSOM API is different from the Azure API. When migrating using the CSOM connection only, the target user account can be in an email format. On the other hand, when migrating using the Azure migration pipeline, the target user account needs to be in claims format.NOTE: Migration of a single item is always through the CSOM connection only so the issue would not occur.
When migrating using the CSOM connection with the Azure migration pipeline, change the target user account from email to claims format. Below is a sample user mapping file:
For migrations using the CSOM connection only without using Azure import pipeline:
For migrations using the CSOM connection with the Azure import pipeline:
If the Source site uses Claims-based authentication it is required to add the correct encoded claim, most used Type of claim is "Windows User": i:0#.w|Metalogix\User1. In the mapping file it should look like this: