Fix disk error code 0146

Error code 0146 on Dell laptops and desktops is reported by Dell’s built-in hardware diagnostics and means that the hard disk’s self-test log has recorded errors – a warning sign that the drive may be starting to fail.

When the system will not boot, the files are often still on the drive. Before reinstalling Windows, see how hard drive recovery works, starting with a free diagnosis.

The underlying cause is often bad sectors or wear on the drive itself, although corrupted system files and malware can make the symptoms worse.

In practice, the computer freezes often and programs stop responding for long periods.

You may also see blue screens and a range of other Windows problems. If the cause isn’t dealt with in time, you could lose the data stored on the hard disk, and the laptop or computer as a whole will become increasingly unreliable.

In this article, we look at what can cause this error and how to deal with it – starting with how to keep your data safe.

01What causes hard disk error 0146?

Error code 0146 can have several causes. These are the most common:

Bad sectors

Bad sectors are a common problem with hard disks (HDDs), which store data on platters spinning at high speed, written and read magnetically by heads that float just above the surface.

The surface is divided into sectors, so it is possible for only part of the data to become unreadable.

Bear in mind that a file is not always stored in consecutive sectors: as the disk is used, its pieces end up spread across the platters, and the drive has to read all of them to put the file back together.

So even a small damaged area can be enough to make a file – or a part of the operating system – unreadable, preventing processes from completing correctly.

SATA mode (IDE or AHCI)

The problem may also come from the SATA mode set in the BIOS – IDE or AHCI – which defines how the computer communicates with its storage drives.

IDE (here, Integrated Drive Electronics) is a compatibility mode that emulates the older IDE interface, also known as PATA (Parallel ATA); AHCI (Advanced Host Controller Interface) is the native standard for SATA (Serial ATA) drives.

Follow the recommendations for your motherboard and drive: AHCI is the best option whenever the motherboard supports it. Note that switching the mode on a computer where Windows is already installed can stop it from booting, so only change it if you know which mode was set originally.

BIOS error

Remember that the BIOS (or UEFI) is the firmware that initialises the hardware when the computer is switched on, finds the operating system on the disk and starts it.

That’s why incorrect BIOS settings can stop a component from being recognised properly, preventing the computer from starting normally.

If the hard disk is not working, check the BIOS settings to make sure they are correct and that all of the computer’s components are detected.

Physical damage

Hard disks are delicate devices: some models are a little sturdier than others, but all of them can be physically damaged quite easily.

This can be caused by a knock, a sudden movement or simply wear on internal components.

Keep in mind that a hard disk has a limited lifespan – usually a few years of use – and the older it gets, the more likely it is to start producing errors.

Physical damage puts the stored data at risk and can trigger many errors, including 0146.

Virus infection

A virus can damage or alter operating system files.

Fortunately, this is less common nowadays, thanks to the regular security updates for Windows and antivirus programs.

Even so, as operating system defences have improved, malware has also become more sophisticated, so it’s a good idea to scan your files regularly.

Corrupted system and log files

Windows relies on its system files, as well as log files, to work properly.

These files are important and can be damaged by errors while data is being written, such as a sudden power cut, a hard disk fault or a virus.

A single damaged file of this kind can be enough to cause errors across the whole operating system and affect its performance.

02How to fix hard disk error code 0146 on a Dell PC

There are several things you can try to fix error code 0146 on a Dell PC. We’ve put together 7 of them, step by step. Before you start, copy your important files to another drive: if the disk is failing, every hour of use increases the risk of losing data.

Run a full system scan

A virus or other malware can corrupt files on the hard disk and contribute to error 0146.

To rule this out, install a reliable antivirus or update the one you already have, then run a full system scan and remove any infection it finds.

Run Disk Cleanup

Another step you can try is to clean up the disk.

Windows includes a tool called “Disk Cleanup”, which removes unnecessary files from the hard disk to free up space.

It deletes temporary files, empties the Recycle Bin and removes unneeded system files, some of which may be involved in the problem. Make sure there is nothing in the Recycle Bin you still need, and remember that freeing up space does not repair a disk that is physically failing.

Here’s how to run Disk Cleanup:

• Go to “Start”, type “Disk Cleanup” and press “Enter”;
• Wait for Disk Cleanup to scan your drive(s);
• When the scan has finished, tick “Temporary files” (and any other categories you want to remove) and click “OK”;
• Click “Delete files” to confirm.

Repair system files with SFC

Windows includes a tool called System File Checker (SFC) that checks the integrity of all protected system files and repairs damaged ones whenever possible.

Here’s how to run the sfc /scannow command in any version of Windows:

• Go to “Start”, type “cmd” (without the quotes), right-click “Command Prompt” and select “Run as administrator”;
• Type the command sfc /scannow and press “Enter”;
• Wait for the scan to finish and restart the computer. Any corrupted system files that SFC finds are replaced with clean copies kept by Windows.

Run the PSA diagnostics

Dell laptops and desktops include pre-boot diagnostics (32-bit Diagnostics, PSA or ePSA).

Newer models also come with the Dell SupportAssist diagnostics, which help identify hardware problems.

Here’s how to run the PSA diagnostics:

• Turn off the laptop (make sure the AC adapter is plugged in);
• Turn the laptop on and press “F12” repeatedly as soon as the Dell logo appears;
• Wait for the “One Time Boot” menu to appear on the screen;
• Select “Diagnostics” and press “Enter”;
• The diagnostics will start automatically. Follow the on-screen instructions and write down any error code shown – if the hard disk test fails, the drive needs to be replaced, so make sure your data is safe first.

Reset the BIOS settings

Incorrect BIOS settings can seriously affect your system’s performance.

That’s why it’s worth checking the BIOS settings: restoring them to their defaults can help resolve error 0146.

To do this, follow these steps:

• Restart the computer and press “F2” repeatedly while it starts up, until the BIOS settings appear;
• Select “Restore Settings”, “Load Defaults” or a similar option to reset them. Afterwards, check that the SATA mode is still the one Windows was installed with; otherwise, the system may not boot.

Run System Restore in Safe Mode

System Restore can also fix error 0146 on a Windows PC when the cause is a software change.

Safe Mode is a Windows diagnostic mode that starts the PC with only the essential files and drivers.

This means you can run System Restore in Safe Mode to take the system back to an earlier restore point without the error appearing at startup.

Here’s how to do it:

• Open the advanced startup options: in Windows 10 and 11, hold down “Shift” while you click “Restart”;
• Go to “Troubleshoot” > “Advanced options” > “Startup Settings” > “Restart” and press “4” (or “F4”) to start in Safe Mode;
• Go to “Start”, type “system restore” (or “rstrui”) and press “Enter”;
• Follow the instructions to choose a restore point;
• Wait for the process to finish and for the computer to restart.

Make sure you choose a restore point dated before the error first appeared. Remember that System Restore does not change your personal files or documents, although it does remove programs and drivers installed after that date.

Start your PC in Safe Mode and perform a clean boot

Starting the system in Safe Mode and then doing a clean boot – with third-party programs and services disabled at startup – can also help resolve error code 0146.

To do this, first disconnect all peripherals from the computer, such as the printer, Wi-Fi adapter or modem, and then follow these steps:

• Shut down the computer;
• Turn it back on and open the advanced startup options (in Windows 7, press “F8” repeatedly during startup; in Windows 10 and 11, hold down “Shift” while you click “Restart”);
• Choose “Safe Mode with Networking” and sign in to Windows;
• Press the “Windows” key + “R”, type “msconfig” in the window that opens and click “OK”;
• In the “System Configuration” window, open the “General” tab and select “Selective startup”;
• Untick “Load startup items”;
• Open the “Services” tab, tick “Hide all Microsoft services” and click “Disable all”;
• Restart the computer and check whether the error has gone.

03Conclusion

Hard disk error code 0146 is common on Dell laptops and desktops and means that the drive’s self-test has recorded errors, which can end in hard disk failure.

It can be caused by bad sectors, an incompatible SATA mode in the BIOS, incorrect BIOS settings, physical damage, a virus infection or corrupted system files.

To deal with error code 0146, you can run a full system scan, clean up the disk, repair system files with SFC or run the PSA diagnostics.

Other options are to reset the BIOS settings or to use System Restore in Safe Mode, with or without a clean boot.

If none of these solves the problem, the best course of action is to have the data recovered and replace the hard disk.

And that’s where Bot can help!

We have more than two decades of experience in recovering data from hard disks, even when the drive has already been opened by another repair service.

What’s more, diagnosis is free and our standard turnaround for the diagnosis and quote is up to 48 hours.

For your convenience, we offer free collection of your device (islands not included) – or, if you prefer, you can bring it to one of our reception points in Lisbon, Coimbra, Porto and Braga.

Count on our 96% success rate: Start your data recovery with us now!