Recently, I ran across an issue deploying DirSync at a Customer.
The installation went well, but running the “Directory Sync Configuration Wizard” failed with the error message “There is no such object on the server”.

Investigating the event logs, the configuration seemed to stop at the following event:

Looking in to AD after the wizard had failed, no account had been created.
I then noticed that the Users container in the domain root was missing.
Since it is there DirSync by default tries to create the sync account and the container didn’t exist, it failed.

After recreating the Users container (can be done with either AdsiEdit or PowerShell), the Configuration Wizard completed successfully.

Recreate the users container with PowerShell

New-ADObject -Description "Default container for upgraded user accounts" ` 
             -Name Users ` 
             -Type Container `
             -ProtectedFromAccidentalDeletion $true

Hope this helps you if you are running in to this problem!

/Johan