From some of my testing, it seems that rsync is sending whole files, rather than just the changes. On small files, this doesn't really matter, as it is probably more efficient to do it this way. However on larger files (e.g. PST's), sending the whole file uses up a lot of bandwidth.
I have tried using the '--no-whole-file' switch, but this doesn't seem to make any difference.
Looking at the log file the "problem" appears to be that rsync is unable to match any of the data in the source and target file, and as a result re-sends the whole file to the target. Is this normal behaviour for PST files?
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