There is a Roaming user profiles known issue that Microsoft describes as follows:
On a computer that's running Windows 10 Version 1803, you experience logon or logoff delays when you use roaming user profiles. You also receive the following error message: Your roaming profile was not completely synchronized. See the event log for details or contact administrator".
https://support.microsoft.com/en-au/help/4340390/roaming-profile-was-not-completely-synchronized-error-and-logon-logoff
If think you are experiencing this issue please let me know.
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