If you get the error message “The disk cannot be written to because it is write protected” when trying to write data to a disk, there are a few potential causes and solutions to try:
Quick Overview
The most common reasons for the “disk is write protected” error are:
- The disk has a physical write-protect switch enabled
- The disk partition is marked as read-only
- The NTFS permissions are restricting write access
- The disk has corrupted filesystem structures
- Antivirus software is blocking writes
To fix the issue, first check for a physical write-protect switch on the disk and disable it if enabled. Then run CHKDSK to check for file system errors. If the drive permissions are restricting access, modify the security settings. Disable or exclude the disk from antivirus scanning. As a last resort, backup data and reformat the disk to repair any filesystem corruption.
What Does “Disk Is Write Protected” Error Mean?
The “disk is write protected” error occurs when the operating system attempts to write data to a disk but is unable to complete the write operation. It is typically accompanied by error codes such as “data error (cyclic redundancy check)” or “Requested write operation failed”.
When this error occurs, it means something is preventing the OS from modifying data on the disk. The disk itself is being protected from writes by some means. This write protection can be enabled in several ways:
- A physical switch or tab on the disk itself is enabled
- The disk partition is marked as read-only in the partition table
- User permissions are restricting write access to the disk
- Antivirus or other security software is blocking writes
- The disk has file system errors that prevent writes
The core issue is that for some reason, the normal write operations to the disk are being prevented at some level. Tracking down what exactly is blocking the writes is key to resolving the problem.
Common Causes of “Disk Is Write Protected” Error
There are a few common causes that can lead to seeing the “disk is write protected” error message:
1. Physical Write Protect Switch
Some removable storage devices like SD cards or USB flash drives have a physical switch or tab that controls write protection. If this switch is slid to the lock position, the device is rendered read-only and any attempt to write will fail with a write protected error.
Checking for a physical write-protect lock and disabling it if enabled is one of the very first things to check when encountering this error message.
2. Partition Marked Read-Only
Another potential cause is if the disk partition is marked as read-only in the partition table. This often happens if the disk was originally setup as a bootable device. The boot partition may be intentionally marked read-only to prevent corruption.
Using diskpart or disk management utilities, verify the read/write status of each partition on the disk. If set to read-only, the partition attributes can be modified to allow writes.
3. NTFS Permissions
If using a Windows NTFS formatted disk, the NTFS permissions settings could be restricting write access. The user account being used may not have sufficient permissions to modify files and folders on the disk.
Check the Security tab properties of files and folders on the NTFS volume. Make sure the user account has full control or modify rights in order to allow write operations.
4. Antivirus Software
Antivirus scanners and other security tools can sometimes interfere with normal disk write operations. Real-time protection may be blocking writes to certain files it deems risky.
Try disabling the antivirus completely and attempt the disk write again. If successful, add exceptions to the antivirus for any files or disk volumes causing issues.
5. Disk Filesystem Errors
Filesystem corruption or damage can also lead to a disk being write protected. The filesystem structures themselves may have errors that prevent writes.
Use CHKDSK in Windows or fsck in Linux to scan for and repair any filesystem problems on the disk partition experiences issues.
How to Fix “Disk Is Write Protected” Error
With the most common causes in mind, here are the general steps to try when troubleshooting the “disk is write protected” error:
- Check for a physical write protect lock – Disable any physical lock switches on the disk itself to allow writes.
- Verify partition attributes – Use diskpart or disk utility tools to check if the disk partition is read-only and change to read/write if needed.
- Check NTFS permissions – Confirm the user account has modify permissions on any restricted files/folders on an NTFS filesystem.
- Exclude disk from antivirus – Add the problematic disk to antivirus exclusions to avoid any false positives.
- Run CHKDSK – Use CHKDSK in Windows or fsck on Linux to check for and repair any filesystem corruption.
- Reformat disk – As a last resort, backup data and reformat the disk to fix persistent filesystem errors.
Additionally, trying the disk on another computer can help determine if the issue is localized to one machine. If the disk functions normally on a different system, it points to a software or driver issue instead of a physical disk problem.
Going through each of these steps methodically will help uncover what is causing the write protection on the disk and correct it.
Detailed Troubleshooting Steps
Here are more detailed steps to troubleshoot the “disk is write protected” error:
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Examine disk for physical lock switch – Remove the disk and inspect the housing, connector, and board for any physical tabs or locks that prevent writing. Move any locks to the unlocked position allowing full read/write access.
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Connect disk to another computer – Try connecting the disk to a different computer. If successful, the issue may be localized system driver or software conflicts.
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Check disk partition status – Use the diskpart utility in Windows or fdisk in Linux to check the status of each partition on the disk. Look for any partitions marked as read-only and change to read/write.
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Review NTFS security settings – For NTFS drives, open the Security tab of files/folders experiencing issues. Confirm the current user has Modify access rights. Add permissions if needed.
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Update disk drivers – Update the drivers for the disk controller and storage volumes in Device Manager. Old, corrupt drivers can prevent proper write access.
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Disable antivirus software – Completely disable any antivirus scanners or other security tools running on the system. Try the disk write operation again without these running.
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Run CHKDSK / Check Disk – Use CHKDSK in Windows or fsck on Linux to scan for and repair any file system corruption or errors on the disk.
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Reformat disk – As a last resort if all else fails, backup data on the disk, reformat the drive and attempt the write operation again.
Bypassing Physical Disk Write Protection
On some hard drives and external SSDs, there may be a physical write-protect switch preventing writes even if the software believes the disk is read/write.
In these cases, the only option is to disable the physical write protection on the disk itself. This requires locating and changing a physical slider, switch or jumper on the disk housing or circuit board.
Examples of bypassing physical write locks:
- Moving slider switches on external USB drives from Lock to Unlock position.
- Removing foam tabs covering disk controller pins to re-enable writes.
- Changing jumper pins on hard drive circuit boards to remove write protection.
- Closing external enclosure tabs allowing full access to USB drives.
Consult your specific disk device documentation for details on how to disable any physical write protection mechanisms built into the hardware.
Removing NTFS Permissions Write Protection
If using an NTFS formatted disk on Windows, file and folder permissions may prevent write access even if the disk partition itself is read/write.
To allow disk writes on an NTFS volume, ensure the current user account has the proper permissions.
Steps to fix permissions errors:
- Open My Computer and right-click on the affected disk or folder.
- Select Properties > Security tab > Advanced.
- Click Change Permissions.
- Confirm the user account performing the disk write has full access.
- Apply any permission changes needed to allow writes.
Also check that the NTFS partition is not flagged as read-only under Partition Settings. All partitions should be read/write unless intentionally set to read-only mode.
Using Antivirus Exclusions for Disk Access
Antivirus software and other security tools can occasionally block legitimate read/write operations to a disk. If writes fail only when antivirus is active, add the disk to the exclusion list.
Exclude disks from antivirus scanning:
- Open antivirus settings and navigate to scan exclusions options.
- Add the problematic disk volume to exclusions.
- Save changes and retry the disk write operation.
In some cases, fully disabling antivirus may be required as a temporary troubleshooting step to verify it is the cause of the write protection.
Remember to re-enable antivirus once testing is complete and apply any needed exclusions.
Fixing Disk Filesystem Errors
If a disk has file system corruption or damage, it can sometimes result in write protection errors. Fixing the filesystem problems may resolve the issue.
Use CHKDSK in Windows:
- Open command prompt as admin.
- Run “chkdsk X: /f” where X is the drive letter with errors.
- Restart computer and rerun chkdsk to repair any problems detected.
Use fsck in Linux:
- Open terminal console.
- Unmount the partition with errors – “umount /dev/sdb1”
- Run “fsck -f /dev/sdb1” to scan and repair filesystem.
- Remount partition after repairs complete.
This checks the filesystem structures for errors and attempts to repair any corruptions or inconsistencies. Hard resets during writes, sudden power loss, or improper shutdowns can sometimes damage filesystems leading to write issues.
Reformatting Disk as Last Resort
If all other troubleshooting steps fail to resolve the write protection errors, reformatting may be required. This wipes and recreates the filesystem, potentially fixing any deep corruption.
Important: Backup any data first before reformatting as it will be erased.
Steps to reformat disk:
- Use backup software to create copies of all files on the disk.
- Open Disk Management in Windows or a tool like GParted in Linux.
- Delete existing partitions on the disk.
- Create a new partition filling the disk space.
- Apply a filesystem format like NTFS or EXT4.
- Restore data from backups.
With fresh filesystem structures, the disk should now allow proper write access again. This provides a clean slate eliminating any deep-seated errors.
Conclusion
The “disk is write protected” error often arises due to user permissions, physical hardware switches, partition attributes, antivirus software, or filesystem corruption. Going through a structured troubleshooting approach helps isolate the root cause.
Always start by checking for any physical write protection switches on the disk itself. Then verify the partition is set to read/write, permissions allow access, and antivirus tools are not interfering.
Use CHKDSK or fsck to repair any filesystem errors or corruption that could prevent writes. And reformatting as a last resort provides a completely fresh start.
With focus on the most common causes, the sources of disk write protection can be uncovered. Carefully enabling writes again resolves the error and restores full read/write access.