You should check to make certain your drive isn't full (both slice 0 and slice 3), and then use the fsck (file system check) command on BOTH slices on the drive. You can only fsck the root partition from within the startup shell, in order to fsck any other slices you will need to launch A/UX and use the fsck command. If this does not work, you will need to reformat the drive and re-install A/UX.
WARNING: You need to have a back up of your hard drive before formatting. The format process will erase all data.
You may find when you run the fsck command on slice 0 again, it will report dirty even though it was not used since the previous clean up. Then run the fsck command on slice 3. On completion of fsck, if you see a message that says "FILE SYSTEM WAS MODIFIED" it is recommended that you run fsck again using the same command. You want fsck to make a complete check without any changes.
You should now be able to install A/UX.
If your hard drive has slice 0, and also has a slice 3 data partition which is dirty, the installer may believe that slice 0 is dirty too. Somehow, slice 0 gets flagged as dirty as a result. You will need to run the fsck command on both partitions. This is an anomalous behavior.
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