I've got a Compaq Presario CQ58 which displays error message 0xc00000e9. On researching the problem, one suggestion is that the hard drive may have gone dead. I have changed the hard drive for a known good one and the laptop works as expected. Can I assume that the hard drive needs replacing or is there still the possibility that it works? If the problem is much simpler, how can it be remedied? Update: I've run system diagnostics which shows Smart Check has passed (?) but Short DST hard drive test has failed. F8 gets to the safe mode page but when SM with command prompt, or other option, Windows files are loaded and after a few minutes the same error page loads (Status 0xc00000e9 I/O error has occurred) and I cannot types in chkdsk /r. I have a SATA caddy on order so as to (try to) copy files later but still need to identify whether or not it is the Hard Drive.