Now to resolve this, MFTPS service account should have full control access to the "TransactionNumber" registry key.
To do this, Open the Registry Editor and find the TransactionNumber at HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Proginet\CyberFusion Server\TransactionNumber.
Assign the full control access to the user account under which MFTPS service is running. Restart the MFTPS service once changes are done.
Note: Create back up before making any changes to the registry key.
Attaching the screen shot here for reference.