You must have had the "Password Checking" enabled in A/UX 3.1 Startup.
In A/UX 3.1 it has been reported that if the "Password Checking" was turned ON in A/UX Startup, the MacPartition (in AWS 95 boot volume) will be hidden from all users, including the root super-user. This symptom has been submitted as an enhancement request since AWS 95 A/UX 3.1 was released.
This behavior has been changed with the release of the AWS 95 Tune-Up 2.0, which is expected to be released in the next couple of weeks.
The only workaround, until AWS 95 Tune-Up 2.0, is to disable "Password Checking" in A/UX StartUp.
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