I'm trying to conduct a test migration by migrating on-prem Sharepoint document library data to an Sharepoint online list.
Everything seems to be fine when I prepare the data without specifying UserMappingFile parameter for ConvertTo-SPOMigrationTargetedPackage command. The data is successfully imported to target library.
But when I try to specify a mapping file then I cannot seem to figure out what data should in contain for OnPremSid or how the CSV structure should even look like.
When I create a CSV with needed header row and add user specific rows then the command fails with
ConvertTo-SPOMigrationTargetedPackage : Failed to parse user mapping file. There are too many items on the line with textTried then to format the document so that all rows are on same line and it seemed to fix the error but mapping part still gives error that not all users where mapped. This seems to be related that the converter cannot find correct SID-s. Tried to make correct CSV file with this powershell script https://spwondering.wordpress.com/2016/05/11/sharepoint-online-migration-user-profile-mapping-file/ but still no luck. Has anyone managed to get a hold on the migration so that he/she converted local domain users to O365 users?