'Loading PBR for descriptor 2...failed' horrors

Hi all,

I've been lurking on this site for the past few months prior to buying a notebook and have just recently bought the Dell XPS M1210 in Japan. To cut a long story short I followed the great reinstall instructions on this site to partition, format and reinstall and fix media direct. Everything was fine until I screwed up and needed to reinstall windows again. (I'll spare you the details of how I managed to do this in less than a week of the first cleansing of new laptop bloatware... ; )

Anyway, I had just finished putting all the necessary drivers onto XP SP2 and went to fix media direct. I followed the same pattern as the first time but this time after repairing Media Direct (with a custom-created CD as recommended) windows failed to load, instead displaying the message in this post's title: 'Loading PBR for descriptor 2...failed'

I reinstalled *again* and the same thing happened after I attempted to fix media direct, so I'm confident no 'send back to Dell' solution is required. After reading a fair amount of information here and on the rest of the internet, I think it's my partition tables.

Upon the second reinstall, I noticed my second partition (D: ) drive had moved to become the C: drive, and susbequently the OS was now on the D: drive. This is the current situation.

So:

I originally left and have not since touched the Media Direct partition 1 as recommded in the 'How to format XP on Dell laptops' post. Hence I now have something like the following: (HDD 120GB as quoted with the laptop)

Partition 1: Original 47Mb(?) Dell-created partition
Partition 2: C: My own 'disk' for files, approx 36Gb
Partition 3: D: Windows XP (80Gb approx)
Partition 4: The 8Mb small partition I see when loading from the XP disk

*******

As you can probably tell, I have little knowledge of partitioning and fixing boot problems, so I wanted to ask for help/suggestions here before attempting to fiddle with the boot.ini file and others in an attempt to reorder my partition tables. As far as I can tell, I only need to swap partitions 2 and 3 in order for the Media Repair fix to work. Since Media Repair requires the OS be on partition 2, am I right?

*But* since I have already used Media Repair, what changes (if any) will it have made to my C: drive (the 36Gb partition I want to keep free of all OS and boot-related material). I really, really want to avoid having to delete both partitions 2 and 3 again and reinstalling XP again, because it involves moving all my files off the C: drive and too much time. I've already reinstalled 3 times since I received the laptop last week!

**********

So, can anyone recommend what to do and give me a simple explanation of how to do it? I can create a USB flash boot disk if necessary, but a creating a bootable CD would be difficult in my current environment.

Thanks in advance, and I apologise if this question has already been thoroughly answered elsewhere. Please direct me to the information if necessary. However, I have already read this post: http://forum.notebookreview.com/showthread.php?t=49086&page=9

Thanks again

 

*Bump* Sorry to pester, but I'd really appreciate some help ^^

 

Here's the current status:

I've downloaded and created a flash boot drive and examined my partition tables. They look like this:

DE 00 0 1 1 5 254 63 63 96327
0F 80 6 0 1 1023 254 63 96390 155653785
07 00 1023 0 1 1023 254 63 155750175 75730410
0 0 0 0 0 0 0 0 0 0

First is 47MB
Second is around 80GB
Third is around 36GB
Fourth is empty

So actually it turns out that, according to ptedit, XP *IS* on the second partition after all, contrary to what I thought. Could it have only been the confused drive letters that caused the PBR errors? I'm not sure what caused it now, nor as fully confident that if I format both partitions and reinstall windows again, that Media Direct won't screw things up again...

Note that partition 2 is marked as 'X extended', though I don't fully understand what that means; something about having several sections on one partition? Third is supposed to be OS-free but is marked with an 07 - isn't that something to do with an active partition..? I'm guessing Media Direct Repair did something to it because it was mapped as the C: drive before things became corrupted.

I managed to change the mapped drive letters later on, but it did nothing. Also I experimented with filling the first line of the partition table with 00 and the XP section with 07 to see if it'd boot, but to no avail. I've also tried FIXBOOT through recovery console and BOOTCFG /REBUILD, without success. All that I can think of now is to try fixing the Master Boot Record, but I'm concerned if I do that that I will give myself more work if I need to reinstall the Media Direct partition - I'm not sure exactly what the MBR command will do to Media Direct, as that's the only thing that boots up right now...

So the repair worked to restore Media Direct functionality but hurt the OS boot... Any ideas..? Any information on the partition tables - someone who can 'read' them?

 

No idea. Sounds like you need to try giving dell a call if they offere support in Japan (which I imagene they do).

 

If you have data you need to get off the drive before wiping it clean again do a google search for the Linux Knoppix LiveCD. You can boot into Linux off the CD and save any data you need to a flash drive. Following that you can use Linux to wipe the drive (if you know how) or do a search for the Ultimate Boot CD on google and use to it fill your hard drive with zeros and reformat. Finally, reinstall windows.

I had something similar happen to me when I tried repairing Media Direct the 1st time. Let's just say after that fiasco I deemed it not worth it and deleted the thing and got some HD space back. The above procedure worked for me.

Oh, and calling Dell won't do a thing. Trust me, I tried.

 

You have a number of issues going on here, so it's hard to give you a simple answer.

Ptedit shows that your partitions are indeed in an odd order, both physically on the disk and in the partition table. It's unusual for someone to deliberately place data partitions ahead of the OS partition, which is what you've done.

The 'active' partition is partition-2 (hence, the "loading pbr 2" msg). But that's an Extended partition, and an Extended partition is never bootable. It's no wonder the system fails to boot it.

If XP is in partition-3, then that's the partition that should be marked 'active'. But from your trials it appears that arrangement of partition table descriptors may be incompatible with the MediaDirect repair utility, which I guess wants XP to be listed second in the partition table.

You could swap the order of the partition table descriptors so that XP is listed second, even though the partition itself is still physically third on the disk. That would reinstate compatibility with the MD repair utility. You would also need to make the corresponding correction in XP's boot.ini file.

However, you've also indicated XP is on the drive letter 'D'. Partitions do not really have drive letters attached to them, so how did you come up with those letters? Drive letters exist "only in the mind of the operating system" that you happen to be booted to, so they can be different depending on how you actually boot when you're looking at the drive letters. IOW, the XP installation CD and the finished XP installation may call partition-3 by different drive letters.

If the finished installation sees itself as 'D' when it boots, you're in for big headaches down the road. The only reliable remedy is a complete reinstall so XP correctly sees itself as 'C', not 'D'.

OTOH, if you only see those drive letters when booting from the installation CD, and the finished XP sees itself as 'C', then you're okay and just confusing everyone with the wrong drive letters. All that matters is what XP sees itself when it actually boots.

 

Hi, thanks for your explanation.

I decided to give up and go for a complete reinstall anyway before I managed to read your post. I don't quite know how my partition tables became that screwed up in the first place though... Perhaps in reinstalling the OS, I accidentally created an extended partition from the exisiting primary one I had my own files on..? Is that possible? I was never given an option on the XP CD to choose between primary or extended when formatting and installing the OS... Not that I remember anyway.

The drive letters came from the OS before I tried fixing Media Direct. The OS was listed on drive D:. But when I went to use recovery console after getting the PBR message and BOOTCFG /scan-ed the disk for operating systems, it came listed as C:. I've no idea what went on with the drive letters...

Prior to reinstalling I tried the FIXMBR command and it just removed the Dell 'failed PBR' screen and left me with a bit of jargon on a black screen. So it didn't help. I still left the 47MB diagnostics partition when I formated again, and I had to reinstall Dell Media Experience, but it fixed things. So using the MBR command didn't render anything permanently irreprable so long as I kept the diagnostics partition it would seem.

I would warn anyone that if they are planning to reinstall XP and split the HDD into two or more partitions then they should probably leave the Dell diagnostics partition intact, install XP on their main partition first and then format their other partitions with Windows Disk manager once they have Media Direct repaired. I'm guessing having multiple partitions confuses Media Direct. Either that or my leaving an old partition and reinstalling the OS did something strange.

Fortunately I'm up and running again now (both XP and Media Direct) after wiping both partitions and reinstalling. I really appreciate your help nonetheless and I learnt a little about partition tables and MBR in the process. Just a little ^^ Feel free to write again if you (or anyone else) can explain what happened here for future reference.

 

"I was never given an option on the XP CD to choose between primary or extended when formatting and installing the OS."​

That's because Microsoft can't install an OS in the extended partition. Other OS's can (linux, for example), but MS has always been restricted in that way.

"Prior to reinstalling I tried the FIXMBR command and it just removed the Dell 'failed PBR' screen and left me with a bit of jargon on a black screen."​

Fixmbr simply replaces the Dell MBR with a Microsoft MBR. But the MBR wasn't your problem. The problem was the partition itself that the MBR was trying to boot, regardless of which MBR you use.

"I would warn anyone that if they are planning to reinstall XP and split the HDD into two or more partitions then they should probably leave the Dell diagnostics partition intact, install XP on their main partition first and then format their other partitions with Windows Disk manager once they have Media Direct repaired. I'm guessing having multiple partitions confuses Media Direct."​

I think that sounds like reasonable advice.

FTR, I don't think it's multiple partitions, per se, that confuses the MediaDirect repair utility. I think it's a main OS partition that is not listed second in the partition table.

I've examined several "repaired" MD systems, and every one has a very basic, elementary MBR that is hard-coded to boot only partition #2. Perhaps this was because every system I looked at just happened to have the OS in partition #2, but OTOH it could be because the repair utility is brain-dead and simply assumes the OS is always in the second partition. This is very different from a "real" MBR, which boots the 'active' partition, irrespective of where it is in the partition table.

 

This strikes me as odd, because XP was definitely on my larger partition (partition 2) which is marked with 80, meaning bootable. 0F marks an extended partition as you explained earlier. But this would mean I did install XP on an extended partition. How did I manage that..? Either that or, during the Media Direct repair, it corrupted the partition table to read partition 2 as an extended partition, which is probably more likely.

The 07 on the third partition marks the formated section as NTFS and 00 meaning non-bootable, so it would seem as though partition 3 was unaffected. I do not know what the DE stands for in partition 1, the diagnostics partition - perhaps Diagnostics..?

My original partition table:

DE 00 0 1 1 5 254 63 63 96327
0F 80 6 0 1 1023 254 63 96390 155653785
07 00 1023 0 1 1023 254 63 155750175 75730410
00 00 0 0 0 0 0 0 0 0

Current partition table (fixed):

DE 00 0 1 1 5 254 63 63 96327
07 80 6 0 1 1023 254 63 96390 149468760
07 00 1023 0 1 1023 254 63 149565150 81915435
00 00 0 0 0 0 0 0 0 0

It's interesting to see the only things that have changed are the sizes of the partitions (deliberate - partition 2 is now about 72GB, partition 3 is 40GB) and that one value on partition 2. From 0F (extended) to 07 (NTFS).

Referenced site: http://www.geocities.com/thestarman3/asm/mbr/PartTables.htm

 

So this is the partition table that actually works correctly? Okay then, partition #2 was not really an extended partition.

I was assuming you created the extended partition #2 and installed XP into partition #3, making it active, and subsequently the MD repair tool forced your active partition from #3 to #2.

But if the above partition table is the correct one, then it looks like you're right--the active partition was always #2 and the repair tool must have changed '07' to '0F'. That doesn't give us a warm and comfy feeling about the reliability of Dell's so-called "repair" utility, does it?