Why is my file read only?
There is several possibilities for the file being read only
If you open a file that is on a CD, it will be read only. You will not be able to modify the existing file. This is because you cannot write to a CD. You will need to save the file to the hard drive, modify the hard drive, then burn it to a CD
The file is being used by someone else
If the file is on a network and the file is open at another location, you will not be able to save the file under the same name unless you have given the file rights. Not all programs have that feature. If you cannot designate that more than one person can write to it at a time, you will have to either wait for the other person to close the file or give the file a new name.
Some programs have the ability to protect the file from modification. This is to make sure the original does not get altered. You will have to save the file under a different name. If you do need to modify the original, you will have to take the protection off. The procedure varies depending on the program so you will need to consult the help file on how to do that.