How do I add permissions via command line for “everyone” on external HDD

Question

I have an external HDD and I kind of messed up the file permissions but when fixing it I thought it is ok bc with my username I can access the files perfectly fine. Now that I use this with two PC (actually ATM I don't have access to my other PC) I can't access these files.

The problem is this directory has hundreds of folders with no permission for "everyone". I would like to give it the default permissions including have all access for the user "everyone". How do I do that via command line for these hundreds of folders?

Answer 1

Use takeown to take ownership of the file

takeown /r /d y /f * 

^ Recursively takes ownership of all files without prompting "are you sure".

Follow it up with icacls set the access control list

icacls * /t  /grant Everyone:F

This will recursively grant Full access to user group "Everyone" to all files in the folder.

Answer 2

Try 'Sharing' the drive with "Everyone". Also, make sure you give read/write access if you want to change anything on another computer. This is how I was able to use my externals on several computers.