Every once in a while, you might run into a problem while installing software in Windows NT. The most common reason is that you don't have administrative rights on that particular machine. Fortunately, this problem is easy to resolve but isn't always so easy to diagnose.
One problem that isn't so obvious is that the config.nt might become corrupt. The file is located in the %systemroot%system32 directory. If you open the file in notepad and scroll to the end, you'll see a line that says something like "files=30." If for some reason the number has some characters after it, remove them and save the file. Then try to install the software again.