To most of you out there, the above string of numbers mean nothing, to me, and the others who find this post through search engines, this is a horrible thing to see on your computer screen. but I have found a fix for it, so don't worry!
In my living room I have a machine running windows MCE 2005. I like it. After installing some patches from Microsoft and doing some minor work to the computer, It started acting funny. The TV output would flicker, so I would have to reboot the computer.
When the computer was booting, after the POST, I would get "L 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99 99" on the screen, and the computer would halt. What an awesome and useful error message!
I found a temporary way around the problem. During boot, I could go into the BIOS, and hit "save and exit", and I was good for one boot. But that's not a solution, that's a hack!
After looking around online, I found that the problem comes from a damaged Master Boot Record (MBR). It can be fixed by booting up from a Windows 2000, or Windows XP CD, going into the Repair Console, and running the "FIXMBR" command.
After I did that, I was able to boot up like normal. I fixed my MCE video flicker problem by updating my NVIDIA Drivers. It feels good to figure things like this out; it makes me feel like I'm actually winning, for a change.

August 24th, 2006 at 4:53 pm
Thanks for posting this. I haven’t seen this error in years, and was surprised when I saw it this time. The last thing I wanted to do was reinstall the OS (again) on this ancient box I inherited.
Since This happened to me on a linux box, I thought I’d contribute. The principal is the same, you have to fix the mbr. If you’ve installed your boot loader to MBR, which is common for multi-boot systems, You’ll have to boot from your install cd (or floppy) and reinstall your boot loader. Depending on which OS you’re using, this may be a bit tricky. You may have to go through your setup menu again, specify your target partitions, (don’t format, that defeats the purpose of trying to fix the mbr) and then install your boot loader.
April 21st, 2007 at 1:59 am
Big thanks for this inforamtion. It was really useful.
May 12th, 2007 at 1:34 pm
[...] on my teeny-weeny cell phone screen, I found (and was actually able to read, after a fashion) this post, which reassured me that this was not a virus or any such thing - just a hexadecimal error message. [...]
June 21st, 2007 at 1:45 pm
hey if you could give me a email or something im having the same issue yet it doesnt fix the problem but it gives me a BSOD and reboots my computer instantly now
June 26th, 2007 at 7:17 pm
You are the best!
June 28th, 2007 at 9:34 am
please help, is there any tools to fix this problem under unix? i also get this message, and my computer haver no cd drive, and i can’t afford an internal one.
August 21st, 2007 at 5:25 am
i’m having the same problem but i don’t have the windows xp cd. i can get one but will i be able to save the data on my hard drive if i boot via the CD?
March 2nd, 2008 at 1:19 am
God bless google and God bless your good self for posting a Fix.
March 25th, 2008 at 12:46 pm
Thank you SO much Josh! You just saved me 6 MORE hours of pulling my hair out and puzzling over this one!
Regards, Respect, and Thanks Again!
Tigger
June 2nd, 2008 at 4:41 pm
If you think I’m going to give a windows install disk that kind of access to my linux boot drive, you’re crazy. They probably broke the damn thing to begin with: #include stdio
if (linux)
printf(”L 99 99 99 99 99 99….
June 3rd, 2008 at 9:04 am
iT’s OvEr 9000!
June 8th, 2008 at 10:24 pm
[...] computer is broken Tried to start is this morning but didnt work..now it seems to be this [...]
June 23rd, 2008 at 1:29 am
Thank you for this help!
Thank you Thank you Thank you!
Regards
Wolfgang
June 29th, 2008 at 11:41 pm
I have had a similar problem a few days ago, when I connect non-bootable HD as master drive