Paste preview for new and modified files in Copywhiz.

Question

I have nearly identical directory trees on an external drive and my internal drive. To try to find out the differences, I add all the files from the external drive to  Copywhiz , then I did a Paste Preview. I made sure I selected the option to paste only new or modified files. But when I did a preview, CopyWhiz identified that ALL (100%) of the source files will be pasted, and "0" files to be filtered.

I may not be understanding this right, but I expected only a few dozen files "to be pasted", with the bulk of the files "to be filtered" because they are identical on both drives. I selected these options in the CopyWhiz dialog:

• Paste > Filter tab > Advanced Settings > Automatically identify & paste only new or modified files
• Paste > General tab > Skip if both files are identical and Skip if destination file is newer

 What am I doing wrong? 

Answer 1

Actually, the "Preview" button should be disabled. It is not disabled in the main window. However, it is disabled in the Settings window.

 Copywhiz  cannot find which files to copy and which to skip without comparing the whole set. This is not possible while previewing because it can be really time consuming.

So preview for "Paste only new or modified files" is actually not possible in  Copywhiz .