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This page contains frequently asked questions about AF-disks.
If you want to understand the AF-disk's properties we recommend to read the background first.

1. Can the wrong volume alignment damage the computer?
– No. The alignment affects only the performance of AF-disk.

2. I use Vista or Windows 7. Is it possible to meet with wrong alignment?
– Yes, it is possible in rare cases. For example, AF-disk has been partitioned with outdated software or system has been upgraded from Windows XP.

3. I use Linux. Is it possible to meet with wrong alignment?
– Yes. The alignment requirements is caused by hardware of AF-disk. This problem can appear in any operation system.

4. What software can be used to correct the wrong alignment ?
The disk manufacturers offers the free align tools for its devices:

Also you can re-partition your disk with modern partitioning software (including Windows Vista and Windows 7).
Don't forget to backup your data!

5. Why DiskAT has no information for my external disk?
– Some USB-boxes cannot transfer the required information from disk. You can try to use another USB-box or attach the disk to internal ATA-port of computer.

6. Volume has status "assumed aligned". What does this mean ?
– Such volume is placed on AF-disk with unknown offset. The offset can be unknown for external disk by reasons mentioned in question #5. Also there are disk models that don't report about offset on ATA IDENTIFY command. For example, disk WD6400AARS-00Y5B1 with firmware 80.00A80 has such misbehavior.
As a rule the offset equals to zero. Therefore if offset is unknown then DiskAT checks the alignment in conjecture the offset is zero. The volumes processed in this way have special markup assumed aligned and assumed not aligned.

The status assumed aligned is assigned to the volumes that have right alignment in case of zero offset. In the same way status assumed not aligned is for wrong aligned volumes if conjecture is true. DiskAT versions before 1.0.7 show the unknown-offset volumes with no information status.

7. Can the alignment test damage the disk settings or data ?
– DiskAT doesn't use the commands that modify the settings or data of the disk.
However some old models of USB-boxes can hang at alignment information query. In this case the volumes of disk can disappear from explorer or/and the volumes are seen as RAW in Disk Management window. To restore disk availability one need to disconnect and power off the device for a few seconds.

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© 2011-2012, Sergey Volynkin