How to fix external disk errors without losing data

Versatile, practical and portable, external drives are often used to store our most important data and files.

Errors like this can have a logical or a physical cause, and repeated repair attempts can make things worse. If the files matter, see how external hard drive recovery works, starting with a free diagnosis.

Because they are not always connected to the computer, they are often seen as safer than the internal hard drive, which is more exposed to failures, ransomware and other attacks, viruses and so on.

But that does not mean external drives are risk-free. They can also run into a number of errors, especially when they are not handled with proper care.

These errors range from the drive simply not showing up on the computer to Windows asking you to format it.

So, can you fix these external drive errors without losing the precious data you have stored?

That is what we will look at in this article.

01What types of external drive errors are there?

Each type of external drive error calls for a different solution. That is why you first need to understand what is wrong with your drive and only then decide on the best way to deal with it.

Below are the 9 most common external drive errors:

External drive not showing up

Sometimes you connect your external drive to a Windows PC, or to another device with a USB port, and find that it does not show up.

This can have several causes: partition problems, an incompatible file system, a faulty USB port or cable, or driver problems in Windows. In the worst case, the drive itself has failed.

External disk asking to be formatted

An external drive asking to be formatted is a common error on Windows and usually means the drive’s partition is being read as RAW. Do not format it: formatting erases the data and makes recovery harder.

This error blocks access to the files on the drive and can be caused by:

• An incompatible file system
• A sudden power cut while the drive was in use
• A virus infection
• Bad sectors
• Unplugging the drive without ejecting it safely.

External drive not showing up in Disk Management

When Windows cannot detect your external drive, it does not appear in Disk Management at all.

This can happen for several reasons:

• The USB ports or controller are disabled in the BIOS/UEFI because of incorrect settings
• Connection problems: insufficient power, a faulty or incompatible cable, a problematic USB port, etc.
• Driver problems: the USB or storage controller driver (SATA, if the drive is connected internally or through a dock) is missing or corrupted
• The drive is detected as a foreign dynamic disk.

External drive not showing up on a Mac

Corrupted data is one possible reason why your Mac does not recognize an external drive, but there are others, such as:

• Problems with the USB cable
• Power failure
• Physical damage
• A file system that macOS does not support
• Limitations with NTFS-formatted drives (macOS can read NTFS but cannot write to it natively).

External drive inaccessible

You may plug in your external drive and find that the computer cannot read it, showing an inaccessible external drive error instead.

The operating system can report this error in several ways, including messages such as:

• The parameter is incorrect
• The disk structure is corrupted and unreadable
• Data error (cyclic redundancy check)
• Access is denied
• The file or directory is corrupted and unreadable.

If you see any of these messages, your external drive may have been damaged by repeatedly unplugging it without ejecting it, by a virus infection or by bad sectors on the disk.

To avoid them, make sure you always use the drive correctly.

Dead external drive

More than a simple error, a dead external drive is one that has stopped working altogether.

An external drive is usually considered dead in one of these two scenarios:

1. Logical problem: a damaged file system or corrupted firmware.
2. Hardware problem: a faulty controller board (PCB), a failed integrated circuit (IC) or a mechanical fault.

External drive not initialized

When you try to use an external drive, Windows may show it as “Unknown” or “Not Initialized”.

In this case, you cannot access the data on the drive, and you should not accept the prompt to initialize it, because that writes a new partition table over the old one. The main causes are:

• Outdated driver: an outdated driver can prevent the external drive from being recognized correctly
• Virus attack: a virus infection can sometimes prevent the operating system from reading the external drive
• Partition loss: the drive may show as not initialized after the partition is lost or deleted
• Bad blocks: sectors (or blocks) are the units where data is written on the disk. When they become defective, they can, among other things, prevent the drive from being initialized
• MBR corruption: the first sector of the disk holds the MBR boot code and the partition table. If this sector is corrupted, the operating system cannot find the partitions and the error appears.

Unallocated external drive

An unallocated external drive is one where Windows sees the disk but finds no valid partition on it, so there is no volume or drive letter to access.

This is a serious problem: it usually means the partition table is damaged or the disk is failing, and the wrong action, such as creating a new volume, can lead to permanent data loss.

The most common reasons for a drive becoming unallocated are file system or partition table errors, outdated drivers, and virus or malware infections.

A sudden failure or a power surge can also damage the drive and leave the external drive showing as unallocated.

External drive with a driver error

A driver is a piece of software that lets your computer communicate with your external hard drive.

So errors such as “drive not found” can be caused by missing or corrupted drivers.

In addition, older operating systems such as Windows XP/2000 may not recognize an external hard drive automatically when the hardware is newer than the system.

02How to fix external drive errors

There are various ways to fix external drive errors, and here on the blog you will find plenty of articles explaining how to deal with many of them.

The key is to identify the cause of the error so you can choose the right solution.

However, most of these methods carry a risk of data loss, sometimes permanent.

That is why, before trying any of them, you should recover the data you cannot afford to lose and save it to another, healthy drive.

The problem is that data recovery looks fairly easy, and with so much recovery software available, many people end up trying it themselves.

Without experience, this can damage the external drive even further, make the errors harder to fix and leave the data out of reach for good.

So the safest way to deal with drive errors is to turn to a company that specializes in data recovery, such as Bot, to keep your files and documents safe and get them back.

03Conclusion

For all its convenience, an external drive is not immune to errors. In fact, many different problems can affect this type of drive.

Once you know the cause, most of them can be fixed. However, every fix carries some risk of data loss.

That is why it is essential to recover the data from the faulty external drive before trying any fix.

Both repairing the device and recovering the data may look easy, but both carry the risk of making the problem worse and losing the data for good.

Therefore, the safest way to recover your data and deal with external drive errors is to trust a specialized company like Bot.

Here, your external hard drive is handled by highly trained specialists with extensive experience in recovering data from hard drives.

That applies whatever the make, model or file system of the drive and whatever error it shows.

To give your data the best chance of recovery, our specialists work in a Class 100 (ISO 5) cleanroom, an environment where airborne particles are controlled to protect your drive.

We also understand that your data is urgent. That is why our standard diagnosis is free and takes up to 48 hours.

Trust an experienced team, with more than 200,000 cases handled and a 96% success rate: start your data recovery with us now.