When reinstalling SecureAuth File Sync Service on a SecureAuth appliance that was once a primary, but is now becoming the replication (secondary) node, the following error is presented: "This SecureAuth Appliance is a primary node."
1.) Open the Registry Editor (Start, Run, Regedit)
2.) Expand HKEY_LOCAL_MACHINE\SOFTWARE\SECUREAUTH\
Delete the FileSync Key Key and All Subkeys
3.) Browse to:D:\MFCApp_Bin\Appliance_Sync and rerun the Setup as Administrator.