The File Replication Service may be preventing the computer %1 from becoming a domain controller while the system volume ...

The File Replication Service may be preventing the computer %1 from becoming a domain controller while the system volume is being initialized and then shared as SYSVOL. 
 
Type "net share" to check for the SYSVOL share. The File Replication Service has stopped preventing the computer from becoming a domain controller once the SYSVOL share appears. 
 
The initialization of the system volume can take some time. The time is dependent on the amount of data in the system volume. 
 
The initialization of the system volume can be bypassed by first typing regedit and setting the value of SysvolReady to 1 and then restarting the Netlogon service. 
 
WARNING - BYPASSING THE SYSTEM VOLUME INITIALIZATION IS NOT RECOMMENDED. Applications may fail in unexpected ways. 
 
The value SysvolReady is located by clicking on HKEY_LOCAL_MACHINE and then clicking on System, CurrentControlSet, Services, Netlogon, and Parameters. 
 
The Netlogon service can be restarted by typing "net stop netlogon" followed by "net start netlogon".