Here are a few things you can try. Boot the system, start tapping F8,
eventually, a menu should appear, select "Last Known Good Configuration" and
press enter. If that doesn't resolve it, reboot, start tapping F8 as
before, this time select Safe Mode from the menu and press enter. When you
get to Safe Mode, it should offer the option of going directly to System
Restore, accept the option and try taking your system back to a time prior
to when this began. If the option isn't presented, in Safe Mode, go to
Start\All Programs\Accessories\System Tools\System Restore.
If the neither of the above works, check the two Knowledge Base Articles
below:
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q307545
http://support.microsoft.com/?kbid=318159
If neither article helps, assuming you have an actual XP CD as opposed to a
recovery CD, try a Repair
install as follows:
NOTE, while a repair install should leave your data files intact, if
something goes wrong during the repair install, you may be forced to start
over and do a clean install of XP. If you don't have your data backed up,
you would lose your data should that eventuality occur.
Boot from the CD. If your system is set to be able to boot from the CD, it
should detect the disk and give a brief message, during the boot up, if you
wish to boot from the CD press any key.
Once you have pressed a key, setup should begin. You will see a reference
asking if you need to load special drivers and another notice that if you
wish to begin the ASR (Automatic Recovery Console) depress F2. Just let
setup run past all of that. It will continue to load files and drivers.
Then it will bring you to a screen. Eventually, you will come to a screen
with the option to (1) setup Windows or (2) Repair Windows Installation
using the Recovery console.
The first option, to setup Windows is the one you want and requires you to
press enter. When asked, press F8 to accept the end user agreement. Setup
will then search for previous versions of Windows. Upon finding your
version, it will ask if you wish to Repair your current installation or
install fresh. Press R, that will run a repair installation. From there
on, follow the screens.
If you only have a recovery CD, your options are quite limited. You can
either purchase a retail version of XP will allow you to perform the above
among other tools and options it has or you can run your system recovery
routine with the Recovery CD which will likely wipe your drive, deleting all
files but will restore your setup to factory fresh condition.
I hope you are well backed up because you are in a very precarious
situation. If the files on that system are that important to you and any of
the above resolves the issue, I can't emphasize enough the importance of
backing up your data files and I can't think of a better example of a reason
why than the situation with which you are currently faced. Businesses
should know better than to run without backing up their data.
