Hi @Dario Alexander agudelo gallego ,
I conducted a migration test in my environment. First, the account that logs in to SPMT is the account of SharePoint Online. During the migration process, you also need to enter an account that has permissions to the site of the SharePoint server that needs to be migrated, and then the migration is successful. I did not have the same situation as yours.
According to the official troubleshooting method, this error is generally caused by the fact that the site does not exist, the account does not have permission, or the url is wrong. But you have already checked, it is not these reasons. Then this should be an accident, don't worry, let's do some general troubleshooting to narrow down the problem:
- You try to migrate to another site to see if the problem still exists.
- Switch the migration target site to see if the problem still exists.
- Uninstall SPMT, download it again, and then perform migration to see if the problem still exists.
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