How long do you give the Mac after the arrival of the 'Chooser has quit unexpectedly because ... &c? Given that you are confident that the version of AppleShare (Client) is the most suitable for the OS—and that doesn't always mean the version loaded from an Install CD/Disk—try giving the Mac a few seconds to think, dismiss the error window, and close Chooser. You may be pleasantly surprised to find the server's volume mounted, despite the message, whereafter file exchange proceeds quite happily.

I haven't made a systematic survey of the matter, in but a majority of cases (>50%?) I've lately been finding, in Mac OS 9 and under clients mounting OS 10.4.11 (I haven't tried 10.5) server aliases, that this is the case. If it works for you too, good. If not, check the link above or go back to teeth-gnashing.

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