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Troubleshooting

Each section names a symptom, its usual cause and the steps that solve it. For short answers to general questions, see the Frequently asked questions.

VisualDisk does not start and refers to O&O Defrag​

Cause: The current version only starts when O&O Defrag is registered as its installed host product.

Solution:

  1. Start O&O VisualDisk from the installed O&O Defrag.
  2. If the message remains, repair the O&O Defrag installation.

No drive is available for monitoring​

Cause: VisualDisk works only with detected fixed drives, such as hard disks and SSDs. Without a suitable drive, it cannot start a monitoring session.

Solution:

  1. Check that the drive to be monitored is a fixed drive that Windows detects.
  2. Start VisualDisk again and approve the administrator prompt.

No writes are shown​

Cause: Another drive is selected, the display is paused, or the drive is idle. Write monitoring also needs Windows system tracing, which requires administrator rights.

Solution:

  1. On Write activity, check the selected drive.
  2. If the display is paused, choose Resume.
  3. Wait for normal disk activity, for example an update or a download.
  4. If system tracing cannot start, note the error, start VisualDisk again and approve the administrator prompt.

A process or file name is not available​

Cause: Windows tracing does not always provide a usable process or file name. VisualDisk still counts the observed write.

Solution:

  1. Treat Process name not available or File name not available as missing information; an unknown name is not evidence of malware.
  2. Compare the time of the writes with the activity of the running applications. See Processes and files.

The benchmark reports an inconclusive measurement​

Cause: The benchmark could not produce a fragmented test file that allows a meaningful comparison, for example because free space is insufficient.

Solution:

  1. Open All values and compare the actual extents with the requested fragments.
  2. Free up space on the drive so that the test data and normal Windows activity fit.
  3. Choose Measure again.

Benchmark results vary between runs​

Cause: Background activity or insufficient free space interfered with the measurement. The result applies only to the test files, parameters and system conditions of that run.

Solution:

  1. Close unrelated disk-intensive applications.
  2. Repeat the measurement with the same setup.
  3. Check Individual passes to see the variation. See Benchmark results.

Cancellation does not stop the benchmark immediately​

Cause: Cancel finishes the current pass and removes the temporary test files first.

Solution:

  1. Wait until the cleanup is complete.
  2. Close the application only afterwards, so that no temporary test data remains.

Some values show n/a​

Cause: Some device-level values are not available on every system.

Solution:

  1. Treat n/a as missing measurement data, not as zero activity.
  2. Compare the values that are available, such as throughput and latency.