Please Help! I have a Fijitsu Laptop Lifebook C, and XP home edition will not boot. It hangs on startup and then goes through the System check, and finds no errors, and then just repeats this process. I have replaced the ntldr and ntdetect.com files with fresh files, as this has worked previously with other xp systems, but this time this does not work. When trying to boot into safemode the system hangs on the Mup.sys file. I have also replaced Mup.sys file with a file from a different computer and this also hasn't worked. I am now at a loss now as to what to do next. Any help will be most greatly appreciated.