Dual boot chaos after registry cleanup!

Hi all. Please forgive if this has been covered elsewhere...I have spent ages looking...unsuccessfully. Months ago, I reinstalled XP in a dualboot config, using EasyBCD. (This was because I wished to access several progs still incompatible with Vista.) The two OSs were on separate drives, and it ran beautifully. UNTIL...I did a registry cleanup and defrag two days ago!
When I tried to boot into Vista, the green startup bars started running left to right...and kept on running...and running. After 20 minutes I shut down. I tried to boot in safe mode. After some seconds of loading drivers, this suddenly stopped. After 15 mins, I shut down. I disconnected the XP drive, used the Vista DVD to repair, and can now boot into Vista AS LONG AS THE XP DRIVE IS NOT CONNECTED. (I get a repeat of the bars running on and on and on!)
I tried to repair XP, after reconnecting the drive...both with the Vista drive connected and not connected. When the Vista drive is connected, after selecting XP...nothing happens. Without the Vista drive connected, I get a bootmgr missing message.
I tried to use Partition Magic...then Acronis...to format the XP drive. (After all, I can always put XP and the progs in later!) However after the drive analysis has been running for about 10 secs, the system hangs.
Any suggestions on how to overcome the prob would be really appreciated. (By the way, I restored the old registry but the prob persists.)


Mostly Harmless
Staff member
Hello carinya, welcome to NeoSmart Technologies.

We highly advise our members not to run any of the "registry cleanup" or "registry optimizer" programs - they're often trouble than they're worth; and they can have disasterous results.

Anyway - do not worry, this should be fixable.

It sounds like your BCD hive in the registry may have been corrupted - but I am not certain.

To check, follow the instructions on this page with the XP drive connected: Recovering the Vista Bootloader from the DVD - NeoSmart Technologies Wiki

Can you boot into XP?
Hi Guru...many thanks for the prompt reply. It is really appreciated. I used the Vista DVD earlier. It was after this I was able to boot into Vista. But only if the XP drive was not connected. I assume you suggest I run this routine again..but this time, with the XP drive connected.

Re your question "Can you boot into XP?" I assume you mean after I have run the Vista DVD as suggested? At the moment, I cannot access the XP drive at all!

I'll let you know.


Inserted Vista DVD > Shut down. Connected XP drive. Rebooted to DVD. "Loading files" routine for 60 seconds or so, then the green startup bars started running L to R...and went on, and on, and on, Just like booting from Vista, as explained earlier.
Removed DVD...(Same little green bars still running). Powered off. Disconnected XP drive > rebooted into Vista. All OK!
Opened EasyBCD to proceed with that method of recovery, only to realise the XP drive is not connected. I cannot run my computer while the XP drive is connected! Can you suggest some other way of ..perhaps being able to format this drive from CD/DVD, (bearing in mind both Partition Magic and Acronis caused the system to hang)?
Or maybe...is it possible to know what it is on the XP drive that is causing the problem and , maybe, using another computer to remove the "offending" item...or indeed being able to format the drive? (I can always reinstall XP, and the apps and the dual boot later on)?
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Mostly Harmless
Staff member
This is sounding less and less like a dual-boot problem to me.

It sounds more like your XP drive has gone bad - especially the part about the disk analysis for the XP drive hanging after a couple of seconds.

Stick it in another PC and format it from there, perhaps.
Thanks again CG. I must admit I had been thinking along these lines myself. Perhaps the shock of a reg cleanup was too much for it! just one thing though...when the XP drive is not connected, Vista boots fine. Assuming it has gone bad, would the fact that the XP drive is merely connected...not even involved in the boot process...be sufficient to prevent Vista, which is on the other drive, from booting? Thanks indeed for all your help.


Mostly Harmless
Staff member
Did you clean up the XP or Vista registry?

There are several things that I'm thinking, but I really have no way of pinning it down for you.
1) The XP drive is bad, accessing it freezes your system.
2) The drivers for your XP drive's controller in Windows Vista are corrupt.
3) Invalid FAT, MBR, or Bootsector on XP drive giving you issues.

Only way to find out is put the XP drive in another PC and run diagnostics from there. Try a full-drive format with Acronis, and `chkdsk /r /f` to check if the drive itself is bad.
It was the Vista registry I cleaned up, then defragged, using a well-known and respected, utility. I have just remembered, after this, as a double-check, I ran a newly loaded app, Reg M......c! It found 119 problems. Foolishly, I said "fix 'em all". This was all in Vista, but I am now wondering if it found the other registry (XP) and had a field day there!

The whole scene is not really that drastic...I can still use Vista and, if necessary, can get a new HDD and reinstall XP and non-Vista-compatible apps on that. And then worry the heck out of you when I can't get that setup configured properly!! In the meantime, fingers crossed...I'll let you know. Thanks again for your trouble.
A brief note to advise I popped the "suspect" drive into a friend's PC this morning as slave. On boot, system detected probs in the "newly-installed hardware" and suggested a disk check and diagnostic immediately. All I had to do was press OK! several probs were found, but the disk itself is healthy. I proceeded to format immediately, and now have the drive back in my PC as slave and the system booted beautifully. At the weekend, I'll put XP back in. Thanks again for your trouble. It is appreciated.


Mostly Harmless
Staff member
That's great news!

Just FYI: Your friend's PC ran the `chkdsk /f` command, which is used to search for corrupt files.