Use size + date in combination for determining whether a file is different.

Use both size + date in combination together for determining whether a file is different.

Both must be the same for the file to be considered the same. And both must be different for the file to be considered different.

And what if only one is different?

I was thinking of the TimeDate + FileSize as another option. If one is different, consider it different. If both are different, consider it different.

I suggest an option to pick. FileZilla does that.

You can select this both for synchronization:
https://winscp.net/eng/docs/ui_synchronize

and Compare Directories function:
https://winscp.net/eng/docs/ui_pref_commander

ok. And I can do it where if the TimeDate is different OR the FileSize is different? Either/or, right?

This is a new program to me so I'm just learning it.

Correct.