This worked on Windows 10 but hangs on Windows 11:

rsync -a <local file> <remote host>:<remote directory>

After I terminated the background "ssh" process in Task Manager, this is the output:

rsync: [sender] safe_read failed to read 4 bytes: No child processes (10)
rsync error: error in rsync protocol data stream (code 12) at io.c(276) [sender=3.2.4dev]

The Windows OS build is 22000.918.

Kevin