cant delete some files - help

The Terminal window is quick and effective, but not the safest method for deleting an uncooperative file. So, when deleting files in the Terminal application, it is smart to check carefully that you are deleting the file you intend to, in the correct folder. There is no UNDO. You've heard the warnings.

Rather than try to do the correct cd command and retype the filename, you can type

sudo rm -f

with a trailing space but without pressing return. Then drag the icon of the file you want to delete to the Terminal window. The folder path and filename should be filled in, e.g.,

sudo rm -f ...path-to-folder.../filename

In the Terminal window, see that the folder and filename look right and, if so, press return.

The reason you can't delete the file is probably that you are not the file owner and don't have permission to delete it under Mac OS X. If so, other methods can also be used and would be safer: You can use Mac OS 9. Or you can try changing the permissions on the file in the Get Info window. Or, if you use more than one login name and the file is owned by one of them, log in as the user who owns the file and you should then be able to delete it.

There are three types of users: regular users, administrators, and superusers.

Regular users have access to their own files and user-specific preferences, like their desktop pattern.

Administrators have the powers of regular users, plus control over system-wide settings, such as the options for the login screen. You pick the name of the first (usually only) administrator when you install Mac OS X, so that's the name you are probably using all the time if you have a one-person Mac.

Superusers can do anything, which lets them fix almost any problem (if they know what they are doing) or destroy the system with an ill-advised command (if they don't know what they are doing). There is usually only a single superuser, named root. By default, Mac OS X doesn't let you log in as root. See Mac OS X: About the root User and How to Enable It from Apple's Knowledge Base for the steps to enable root login.

On the rare occasion when you need superuser powers, you can log in as root, or you can use the sudo command in the Terminal application (which lets you perform a single command as a superuser) or you can use the su command (which lets you perform any number of commands as a superuser, until you type exit or close the Terminal window). In all cases when you have to be superuser, you should work carefully and go back to being an administrator or regular user as soon as you are done.