You can implement Session.QueryReceived event to continue on errors.
https://winscp.net/eng/docs/library_session_queryreceived

An example:
https://winscp.net/eng/docs/library_example_recursive_download_custom_error_handling#queryreceived

Good-day WinSCP,

Version 5.17.5., Windows 10 (1803), SFTP, C# scripting (& newbie user :).

Error message:
System Error. Code: 32.
The process cannot access the file because it is being used by another process

Occurs when using "session.SynchronizeDirectories(SynchronizationMode.Both" on a file that is open. Ideally looking for a way to step past the locked file and continue on with remaining files.

Any pointers to posts that might help, gratefully received. Numerous hours on forum and website but not come across the information.

Thank-you.