Hi thanks,
I got the error because I try to write the file in .dll extension (to intentionally confuse the user) for example one.dll, but actually it is a text file. Before I find this, all I did that you have advised, but it throws same error. finally I changed the extension, now its working. And I think there is no need of changing or creating manifest file, because I can run application without that changing anything in manifest file, The only problem is extension(.dll). I think the problem may be still there in Vista X64 systems, because when I googled I got results of problems in Vista X64 systems. (I am running X86).
But I could not share the data file among all users. Now each user will have seperate files, I want to share the data among all the users, How can I do?

Please help me.
Thanks & Regards,
R. Pandiarajan.