Bad Hard Drive Signs and Symptoms - A Guide for Mac Users
Updated October 17, 2014
Hard drives  and SSDs store most, if not all the data on your system, and when they start to have problems, the results may be disastrous. Many people take hard drives and SSDs for granted because they're generally extremely reliable. When problems finally occur,  a user may find themselves losing critical and personal information, such as financial data, years of tax returns, and personal items such as photographs, music, and documents which may suddenly be gone forever, especially if no backups have been made.  It's important to know the signs and symptoms of a possible drive problem because if one is developing, the user will hopefully be able to take the steps needed to minimize potential disaster. Before proceeding, we'll give a quick view of site navigation for this article.
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Brought to you by Scannerz with Performance Probe 2, Phoenix, and FSE for the Mac OS X Operating System. If you have hard drive problems or want to evaluate your drive or system, click on the icon to the left for more information on the Scannerz suite. If you're having performance problems and you're fairly sure they aren't hard drive problems, click on the icon to the right to learn more about Performance Probe 2 as a standalone application.
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General Symptoms of Hard Drive, System, and Software Problems - Problems that appear to be related to hard drives may be caused by the drive itself, supporting system components, or software. We recommend that all readers review this article first because it may provide information that will help you identify whether or not a drive problem even exists. It generally covers the symptoms of a real hard drive or system problem, as opposed to those that may be caused by software problems and the way a user uses their system.
An Overview of Hard Drive Problems - This article describes the problems that a user may encounter that are specific to a hard drive, whether internal or external. This article excludes problems that are caused by other system or software components, and focuses solely on the hard drive itself. This information will be relevant to the following two articles that focus on internal and external drives.
Problems Related to an Internal Hard Drive and its Supporting System Components - This article focuses on problems associated with internal hard drives and their supporting circuitry. If problems seem to exist with an internal hard drive, this article will help you understand whether it's an actual problem with the drive, or whether the problem is with another component in the system.
Problems Related to External Hard Drives and Their Supporting Components - This article focuses on problems associated with external hard drives and their supporting circuitry. External hard drives add several layers of complexity over internal hard drives because they use additional cabling, interface circuitry, and even software in some cases. If you have a problematic external hard drive, you will likely want to read this article.
User Problems - Some problems that appear to be drive related may actually be caused by a users lack of familiarity with the operating system, or possibly their unintentional misuse of the system. Other problems may be caused by software the user has installed on their systems. Review this article if you're not familiar with Mac's or there simply appears to be no solution to what seems to be an existing hard drive problem.
Dealing with Problems - If you think you've discovered the source of your problems, this article will tell you how some, but not all, problems can be corrected if possible. Unfortunately, don't expect miracles here - this article may tell you something you don't want to hear.
Our Product Line Up
We produce products for Mac's that are designed to help people find and correct problems with their systems. Click on the icon to the left of each description to go to the actual product page.
Scannerz with Performance Probe 2, Phoenix, and FSE or FSE-Lite for Mac OS X
Scannerz is our premier hard drive, SSD, and system test tool. Scannerz can find problems other tools on the market miss completely.
Scannerz Lite
Scannerz Lite is a very low cost, much simpler version of Scannerz. If you want a quick and inexpensive way to check a drive, this may be what you're looking for.
Performance Probe 2 for Mac OS X
Performance Probe 2 is a system load monitor that may be used to help identify system bottlenecks caused by memory, I/O, or CPU intensive applications.
Phoenix for Mac OS X
Phoenix is a hard drive and SSD tool that can create emergency backup drives, clone volumes, and help recover data from a failing, but readable drive.
FSE for Mac OS X
FSE is a configurable file system events monitor. It can be used to trace file system activity and help identify applications that may be slowing down your system.
SpotOff 2 with Spot-O-Meter 2 and Spot-O-Meter 2 Mini for Mac OS X
SpotOff 2 with Spot-O-Meter 2 is an mds indexing controller and monitor. Excessive mds is used by Spotlight and Time Machine and may bog your system down..
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