Command Line Usage

FreeFileSync enables additional synchronization scenarios via a command line interface. To get a syntax overview, open the console, go to the directory where FreeFileSync is installed and type:

FreeFileSync -h

1. Run a FreeFileSync batch job

In order to start synchronization in batch mode, supply the path of a ffs_batch configuration file as the first argument for FreeFileSync.exe:

FreeFileSync "D:\Backup Projects.ffs_batch"

After synchronization one of the following status codes is returned:

Return Codes
0 - Synchronization completed successfully
1 - Synchronization completed with warnings
2 - Synchronization completed with errors
3 - Synchronization was aborted

You can evaluate these codes from a script (e.g. a cmd or bat file on Windows) and check if synchronization completed successfully:

"C:\Program Files\FreeFileSync\FreeFileSync.exe" "D:\Backup Projects.ffs_batch"
if errorlevel 1 (
  ::if return code is 1 or greater, something went wrong, add special treatment here
  echo Errors occurred during synchronization...
  pause
)

Instead of displaying "An error occurred!" you can also send an email notification (using a third party tool).

Attention
Make sure your script is not blocked by a popup dialog. Consider the following options when setting up a FreeFileSync batch job:

Enable checkbox Run minimized or have On completion automatically close the results dialog after synchronization.
Set error handling to Stop or Ignore.

2. Start a FreeFileSync GUI configuration

If you pass a ffs_gui file, FreeFileSync will start in GUI mode and immediately start comparison (but only if all directories exist):

FreeFileSync "D:\Manual Backup.ffs_gui"

3. Customize an existing configuration

You can replace the directories of a given ffs_gui or ffs_batch configuration file by using the -LeftDir and -RightDir parameters:

FreeFileSync "D:\Manual Backup.ffs_gui" -leftdir C:\NewSource -rightdir D:\NewTarget

4. Merge multiple configurations

When more than one configuration file is provided, FreeFileSync will merge everything into a single configuration with multiple folder pairs and start in GUI mode:

FreeFileSync "D:\Manual Backup.ffs_gui" "D:\Backup Projects.ffs_batch"