To securely delete a file in Windows, you can use a tool called "sdelete" (Secure Delete). Sdelete is a command-line tool that is part of the Sysinternals suite of utilities. It allows you to overwrite the free space on a disk or specific files so that the data cannot be recovered.
To use sdelete, you will need to open a command prompt window and navigate to the folder where the sdelete utility is located. By default, sdelete is installed in the "C:\Windows\System32" folder.
Once you are in the correct folder, you can use the following command to securely delete a file:
sdelete -p 1 <file name>
Replace <file name> with the name of the file you want to delete. The "-p" option tells sdelete to perform a secure delete by overwriting the file with random data.
You can also use the "-s" option to delete all of the files in a folder and subfolders. For example:
sdelete -p 1 -s <folder name>
This will securely delete all of the files in the specified folder and all of its subfolders.
Keep in mind that securely deleting a file does not guarantee that the data will be completely unrecoverable. There are advanced forensic techniques that can be used to recover data from a hard drive, even if it has been overwritten multiple times. However, securely deleting a file using sdelete or a similar tool will make it much more difficult for anyone to recover the data.