This is a known issue with DART 1.5.3 on any Power Macintosh. DART version 1.5.3 does run a Power Macintosh. The error message is displayed when DART is launched, but if you click OK, DART will continue and everything works as expected. We have not experienced any problems with DART 1.5.3 on a Power Macintosh.
As an alternative to DART, we recommend using Disk Copy, with or without a third party compression utility.
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