Prevent modification to a file in Windows XP or Windows Vista (Readonly property)
Windows XP and Windows Vista let you easily tweak a file's setting to make sure that no one makes any further changes to this file. This can be useful at the office when several people use the same Word document for letters, for example: everyone access the Word document on a shared drive, saves a copy of it on their computer, and customize the letter to fit their needs. To avoid anyone making changes to the original file, you would want to disallow editing the file itself. This tutorial shows you how to protect a file from editing and changes through its readonly property.
Make a file "read only" for all users
To make a file read only and prevent changes to the file, right-click on it and choose Properties.
The file's Properties dialog will open, with the General tab selected by default: near the bottom of this tab, Windows displays the files Attributes. One of them is the file's hidden attribute, discussed in the previous tutorial. Another checkbox visible under Attributes is Read-only, which is unchecked by default.
To prevent any changes to be made to this file, check the Read-only checkbox and click OK to validate the change.
People will be able to open the file and view it, but will need to save it as a copy to be able to save the changes they make to it.
Allow users to edit a protected file previously marked "read-only"
Likewise, if you decide later on to let people edit the file and let them save modifications to the file itself, you would again right-click on it and choose Properties, but this time uncheck the Read-only checkbox to make sure that Windows does not prevent users from saving changes they make to the file.
...This is how simply Windows XP and Windows Vista make it to protect files from editing or saving changes for all users. On a closing note, realize that any user can customize the file's properties to allow changes back: this is not a secure way to protect a file, but it prevents accidental changes (non malicious) from being saved to the file you want to protect.up ↑