Hi, BOO:
Thanks for the reponse. However, let me clarify my question in the
following sequence:
a): I have an original file 1 which is read only;
b): Users open up my original file, modify it, save it as file 2 and
CLOSE it. Then whenever file 2 is re-openned, it should be openned as a
read only file;
c): Users open up file 2, modify it, save it as file 3 and CLOSE it.
Then whenever file 3 is re-openned, it should be openned as a read only
file;and so on!
In summary, I do NOT want users to over-write the existing saved files.
The only thing they can do is to open up any file they want, modify it,
save it as a different file. Once this is done and the file is closed,
they can not come back and modify it anymore!
Thank you so much for your help!

George