Bad Hard Drive Signs and Symptoms - A Guide for Mac Users
Updated March 29, 2015
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. 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.
In the following sets of articles we hope to help you be able to determine whether perceived problems are genuinely being caused by a hard drive or SSD or the problem lies elsewhere. Some problems that have symptoms similar to hard drive or SSD problems may be as harmless as a user being unaware of a particular, or even peculiar characteristic of the operating system or hardware. On the other end of the extreme, some problems that may behave like a hard drive or SSD problem may actually be symptoms of a failing logic board. The last thing anyone wants to do is spend money replacing a drive only to find out there was nothing wrong with their system, or, worse yet, spend the money on a system that's in the process dying.
We are addressing the subject matter using the articles identified below. On the left hand side is an icon associated with the article and on the right hand side is a brief overview of the topic.  To open the web page for each topic, click on the icon to the left of the overview. You can to navigate back to this page or any of the other pages making up this set of articles using an icon menu in the upper left hand corner of each page. The icon menu will use smaller versions of the icons shown below.
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General Symptoms of Hard Drive, SSD, System, and Software Problems - Problems that appear to be related to hard drives may be caused by the drive itself, 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 such problems even exists. It generally covers the symptoms of a real hard drive, SSD, or system problems, 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 or SSD, whether internal or external. This article excludes problems that are caused by other system or software components, and focuses solely on the 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.