What are the symptoms of bad hard drive?

A failing or bad hard drive can have serious consequences, like data loss or complete system failure. That’s why it’s important to look out for early warning signs so you can take action before it’s too late. Here are some of the most common symptoms that indicate your hard drive may be going bad.

Slow performance

One of the first signs of a bad hard drive is a noticeable slowdown in your computer’s performance. Programs and apps may take longer than usual to open and run. Stuttering, lagging, or freezing can occur during normal operations like accessing files, browsing the web, or playing games.

A degrading hard drive slows down your computer because as it fails, it has a harder time reading and writing data. The mechanical parts degrade over time, developing bad sectors and errors. As the hard drive struggles, your operating system ends up wasting time and resources trying to access data from those bad areas.

Strange noises

If your hard drive starts making unusual noises like grinding, buzzing, ticking, whistling, chirping or screeching, that is a telltale sign of a hardware problem. The noises arise from the physical components degrading.

For example, a grinding sound may come from the actuator arm’s read/write head scraping across the platters. Clicking or ticking may indicate the motor is struggling to spin the disks. Any new noise from your hard drive is not normal and indicates imminent failure.

File system errors

As data on a hard drive becomes inaccessible, you may start encountering file system errors. Error messages when trying to access files might say things like:

  • “File not found”
  • “Disk I/O error”
  • “Sector not found”
  • “Read/write failure”
  • “Can’t read from the source file or disk”

You may also see prompts asking you to run disk checking utilities like CHKDSK or fsck to scan for and repair errors. The appearance of file system errors indicates your hard drive is having physical issues reading data.

Bad sectors

Bad sectors are physical areas on a hard drive’s magnetic platters that can no longer reliably store data due to corruption and magnetic issues. Even a single bad sector is a warning sign of bigger problems ahead.

Your operating system may detect bad sectors and mark them off to prevent their use. This is known as “remapping” and uses spare reserve space on the drive. However, remapping does not fix the underlying degradation of the drive’s physical components.

Tools like CHKDSK can scan your hard drive and report any bad sectors. The more bad sectors that develop, the closer the hard drive is to outright failing.

Difficulty booting

If your computer suddenly struggles to boot up properly, takes much longer than normal, or fails to boot at all, the hard drive could be to blame. The operating system may get stuck because it can’t load necessary boot files from a failing drive.

Boot issues don’t necessarily mean complete hard drive failure – an operating system file itself may have become corrupted. But a degrading hard drive increases the odds of boot problems occurring. Difficulty booting is a red flag to look further into your hard drive’s health.

Blue Screen of Death (BSOD)

The infamous Blue Screen of Death (BSOD) usually indicates system instability caused by hardware problems or driver issues. While not a guarantee, BSOD crashes can be related to a failing hard drive.

When the operating system runs into errors reading data from a degrading drive, it may trigger a fatal exception. This halts the operating system and brings up the BSOD with an error message. Common hard drive-related BSOD error codes include:

  • STOP 0x00000024 – NTFS_FILE_SYSTEM

If you start getting BSOD crashes, check for signs of hard drive failure as a potential source.

Disappearing files

When a hard drive starts malfunctioning, you may notice random files sporadically disappearing from file folders and directories. Photos, documents, programs, and other data can seemingly vanish into thin air.

This happens because when a hard drive has bad sectors, the operating system moves data from those sectors to prevent corruption. If the original file system links aren’t properly maintained, the files appear to go missing. They are still physically stored elsewhere, but the operating system loses track of them.

Difficulty writing data

As a hard drive wears out, you may encounter situations where data simply will not write to it anymore. Trying to save a file results in an error about being unable to access the directory or disk.

When mechanical degradation interferes with the hard drive’s read/write heads laying down new data, they cannot fully complete the operation. The inability to modify and overwrite data predicts the hard drive will soon go offline permanently.

Unrecoverable data

No matter the reason for data loss, your hard drive should allow you to recover critical files from a backup or using recovery software. But unrecoverable data is a huge red flag something is seriously wrong.

If you can’t restore deleted files and backups are showing data corruption, the hard drive hardware is failing in a way that garbles file contents. Even reformatting may be unsuccessful since the underlying components can’t read data reliably.

LCD SMART warnings

Many hard drives feature SMART technology which monitors different internal attributes to predict impending failures. If your hard drive shows a warning or error SMART status on boot-up, it’s a clear indication of physical problems.

SMART checks things like reallocated sectors, spin retries, and read errors. Thresholds triggering SMART warnings vary by manufacturer but signal that degraded drive components will soon cause performance issues and potential data loss.

SMART Hard Drive Warning Signs

SMART Parameter Warning Signs
Reallocated Sectors Count Greater than zero bad sectors that have been remapped
Spin Retry Count High number of retries trying to spin up drive platters
Read Error Rate Increasing rate of read errors
Seek Error Rate High frequency of seek errors during platter access

Slow drive self-tests

Hard drives have built-in diagnostics tests that perform read and write operations to scan for bad sectors and physical problems. As your hard drive deteriorates, these self-tests will start taking longer to complete.

Self-tests read from every sector on the drive, so they slow down when encountering areas prone to errors. Slow self-test speeds often precede other failures. Schedule regular drive self-tests to catch this early warning sign.

High drive temperature

Hard drives generally operate within a normal temperature range based on workload. But a failing drive may start running significantly hotter than usual.

Overheating can accelerate component degradation. The higher temperature stresses physical parts like platter motors. Temperature spikes can both contribute to hard drive failure and serve as an early warning.

Monitor your hard drive temperature using disk utilities like CrystalDiskInfo. Make sure your computer case cooling and drive fans are working properly to avoid overheating issues.

Pending sectors

Pending sectors (or uncorrectable sectors) are damaged disk areas that cannot be read but haven’t yet been remapped as full-fledged bad sectors. The hard drive continues retrying to access these problematic areas before giving up and reallocating.

Pending sectors in large quantities point to plenty of read/write problems ahead. If SMART data shows pending sector counts growing, failure is on the horizon. Back up your data immediately.

Data corruption

Opening files only to find gibberish symbols, distorted data, or corrupted content indicates a hard drive problem. The issue arises when the drive inaccurately writes bits and bytes to the disk.

Some amount of corruption may be repairable if you catch it quickly. But reoccurring and widespread corruption usually means the hard drive hardware can’t reliably store data anymore as internal components degrade.


All hard drives inevitably wear out and fail, but catching the signs early gives you the best chance of avoiding catastrophic data loss. Keep an eye out for these common symptoms of a failing hard drive:

  • Slow performance
  • Strange noises
  • File system errors
  • Bad sectors
  • Difficulty booting
  • Blue Screen crashes
  • Disappearing files
  • Difficulty writing data
  • Unrecoverable data
  • SMART warnings
  • Slow drive self-tests
  • High temperature
  • Pending sectors
  • Widespread data corruption

At the first signs of failure, make backups and prepare for replacement. Detecting and quickly responding to hard drive problems can prevent irreparable data loss.