FreeFileSync finds files that are marked different, but when I compare them in
another application, they are the same. But I synchronize them anyway. After
comparing again FreeFileSync finds them different again.
Are There Files Really Different?
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FreeFileSync is right ;) Honestly, you are comparing apples and bananas here:
FreeFileSync has two variants of comparison: 1. file and date 2. content.
Other tools probably use slightly different criteria.
> After comparing again FreeFileSync finds them different again
This is probably because the date and/or filesize have changed during or after
synchronization with FFS. Perhaps you are copying to some network share that
automatically manipulates new files as they arrive.
FreeFileSync has two variants of comparison: 1. file and date 2. content.
Other tools probably use slightly different criteria.
> After comparing again FreeFileSync finds them different again
This is probably because the date and/or filesize have changed during or after
synchronization with FFS. Perhaps you are copying to some network share that
automatically manipulates new files as they arrive.
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- Joined: 15 Jul 2010
Thanks for the fast reply. I am doing a comparison by content. One of the
folders is on an internal drive and the other is on a USB drive. This unusual
behavior does not happen with every file, just a few. I don't think there is a
problem with FreeFileSync because I have seen this with other comparison
utilities. I am asking about it because of the expertise here.
folders is on an internal drive and the other is on a USB drive. This unusual
behavior does not happen with every file, just a few. I don't think there is a
problem with FreeFileSync because I have seen this with other comparison
utilities. I am asking about it because of the expertise here.
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- Site Admin
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> comparison by content
In this case I suggest having a deeper look and see what changes are there
between these files. Pretty much sounds like either a damaged USB stick or
internal drive. Open both files that are detected as different after
comparison with a hex editor and see what the difference is exactly. If its
arbitrarily changed raw bytes you'll have the answer.
In this case I suggest having a deeper look and see what changes are there
between these files. Pretty much sounds like either a damaged USB stick or
internal drive. Open both files that are detected as different after
comparison with a hex editor and see what the difference is exactly. If its
arbitrarily changed raw bytes you'll have the answer.
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It's identical in hex editor.
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>It's identical in hex editor.
Then FFS shouldn't see them as itdentical neither. Do you have steps how to
reproduce this issue?
Then FFS shouldn't see them as itdentical neither. Do you have steps how to
reproduce this issue?
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I vaguely remember something similar happening to me with files that contain
weird characters in their file name. Could this be the problem?
weird characters in their file name. Could this be the problem?
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> weird characters in their file name
Quite unlikely. The means to open a file is via the CreateFile C-API command
which uses wide char Unicode characters. Next bytes are read via the
"ReadFile" function. Assuming that these Windows functions work correctly
there is not much that could go wrong. (I.e. go wrong without notice)
Quite unlikely. The means to open a file is via the CreateFile C-API command
which uses wide char Unicode characters. Next bytes are read via the
"ReadFile" function. Assuming that these Windows functions work correctly
there is not much that could go wrong. (I.e. go wrong without notice)
