The erase command in CMD is used to delete one or more files from a drive. It allows you to permanently remove files and folders from your computer.
What does the erase command do?
The erase command deletes specified files so they cannot be recovered. Unlike simply sending a file to the Recycle Bin, the erase command bypasses the Recycle Bin entirely and performs a direct delete.
This makes the erase command useful for permanently removing sensitive files that you do not want to be recoverable.
How to use the erase command
To use the erase command, open the Command Prompt and navigate to the directory containing the file or folder you want to erase. Then type the command:
erase filename
Or to erase multiple files:
erase file1 file2 file3
You can also use wildcards to erase multiple files matching a pattern. For example:
erase *.tmp
This will erase all files ending in .tmp in the current directory.
Erase command options
The erase command has a few options you can use:
/p– Prompts for confirmation before erasing each file./s– Deletes files in subdirectories in addition to the current directory./q– Quiet mode, does not prompt for confirmations or display messages./a– Indicates an ASCII text file./f– Forces erase even if file is read-only.
For example, to recursively erase files ending in .tmp while prompting for each one:
erase /s /p *.tmp
What happens when you erase a file
When you use the erase command, the file’s entry in the file system is removed. This means it no longer appears in directory listings.
The contents of the file are still physically on the disk until that space is overwritten, but the file system markers pointing to the data are removed. This makes the file’s data inaccessible through normal means.
The space taken up by the erased file is now marked as free space and can be overwritten.
Can you recover an erased file?
In some cases, it may be possible to recover a file erased with the erase command using data recovery software. This scans the raw disk to look for file data that is still intact.
However, the more a drive is used after erasing a file, the more likely the file’s data blocks will be overwritten with new data. So recovery becomes less likely over time.
To maximize the chance of permanent deletion, it’s advisable to also wipe the free space on a drive after using the erase command. This overwrites the remaining traces of any erased files.
Is erase better than delete?
The erase command provides a more permanent deletion than simply sending a file to the Recycle Bin with the delete command. Deleted files can be easily recovered from the Recycle Bin, while erased files bypass it completely.
However, the erase command does not offer complete guarantees of permanent deletion. Use a secure delete tool if you need to wipe sensitive files beyond any chance of recovery.
Proper Usage
Here are some key points on properly using the erase command:
- Run CMD as administrator – This gives erase the permissions it needs.
- Watch out for wildcards – Broad wildcards like *.* can accidentally erase many files.
- Use with caution – Erased files are likely unrecoverable, so ensure you mean to permanently delete.
- Overwrite free space – To fully remove traces of erased files, use a space wipe tool.
Alternative commands
The erase command is not the only way to delete files from the Command Prompt. Here are some other options:
DEL
The DEL command also deletes files and folders. However, it moves them to the Recycle Bin rather than permanently erasing.
rmdir
The rmdir (remove directory) command deletes empty folders. Folders containing files or other folders cannot be removed with rmdir.
deltree
deltree deletes an entire directory tree. It removes the target folder and all its subdirectories and files.
Why can the erased file be recovered?
When a file is erased, its entry in the file table is simply marked as free space – the actual data still remains on the disk. This allows data recovery software to search the raw disk and reconstruct files based on the remaining data.
Full deletion requires overwriting the space used by a file. But simply marking it as free does not touch its actual contents, allowing them to remain intact until overridden.
Ways to securely erase files
If you need to permanently delete sensitive files beyond recovery, using the erase command is not sufficient. Here are some more secure options:
- Use a third-party secure delete tool that overwrites file data.
- Encrypt files before deleting – this scrambles the raw contents into unreadable gibberish.
- Physically destroy the drive – e.g. degaussing, which demagnetizes and erases all data.
- Securely wipe free space – this denies access to residual data left behind.
Specific Uses
Here are some examples of when you may want to use the erase command:
- Removing temporary files – erase can quickly remove files like *.tmp or *.log
- Deleting system files – you may need to erase system files that are locked or in use.
- Wiping free space – the erase command can help wipe residual data from disk.
- Preparing drives for disposal – erase personal files before disposing of an old drive.
- Remote deletion – system administrators can use erase to remotely delete files.
Cautions
Here are some important cautions when using the erase command:
- Erased files may be recoverable – erase does not guarantee permanent deletion.
- Be careful with wildcards – they can end up erasing unintended files.
- Watch out for read-only files – use /f to force erase.
- Don’t erase system files – this can cause instability or failure to boot.
- Have backups – accidentally erased files are likely unrecoverable.
Summary
The erase command provides a way to delete files directly from the Command Prompt in Windows. It skips the Recycle Bin, performing a more permanent deletion. However, erased files may still be recoverable with forensics tools.
To fully obliterate sensitive data, more intensive wiping is required, such as overwriting free space on the drive. When using erase, caution is advised – accidentally erased critical files may be impossible to get back.
Overall, the erase command is a useful tool for permanently removing unwanted files, provided proper care is taken.
| Command | Description |
|---|---|
| erase filename | Erases the specified file |
| erase /p filename | Prompts before erasing each file |
| erase /s *.tmp | Erases .tmp files in subdirectories |
| erase /f file.sys | Forces erase of read-only system file |