Recently I spent way more time that I should have diagnosing my main machine that became unbootable right after uninstalling Acronis Migrate Easy 7.0. I had bought a new hard drive and decided to try using the tool to do a clone of my old drive onto the new one. It appeared to do a fantastic job and initially I was very happy with the result. That is, until I uninstalled the Acronis software and did a reboot…

My machine became unbootable. Every time I booted the machine it got itself in a reboot loop, never getting past the first part of the loading screen. Of course I tried the obvious – hit F8, pulled up the boot menu and selected Safe Mode boot. This helped in as far as I could see each driver it was loading, but as soon as it got to crcdisk.sys it blue-screened on me and that was it.

At this point I was pretty mad but not panicking too much as I knew that the Vista DVD came with a new tool called the Windows Recovery Environment (WinRE). It is designed to automatically detect and repair a bunch of the most common boot problems without any user interaction. I have used it before on a hard drive that became unbootable and it worked wonderfully. Not this time however.

After running the tool and waiting for quite a while for it to do full disk test it failed to fix the problem. So I ran up the command prompt off the WinRE menu and did some digging of my own. The boot settings seemed to be fine – if you want to verify, use bcdedit to check and fix the new Vista boot configurations.

bcdedit

To cut a long story a little shorter, I finally came around to checking the file system filter drivers to see if anything was getting in the way of the file system loading up. As it turned out, this was the culprit. There was an upper filter driver that was still trying to load up that had not been properly cleaned up by the Acronis Uninstall. There was still an entry that was trying to load the driver file snapman.sys but the file was not there anymore. On boot, Windows reads the filter driver entries in the registry and looks for the corresponding driver file, if it is not there, Windows will not be able to load.

Now that we know where to look, the fix is easy:

  1. Insert your Windows Vista DVD and boot up to the DVD boot menu.
  2. Press OK to get past the language settings.
  3. Choose Repair Computer.
  4. Choose cancel if asked to run System Restore
  5. At the menu, choose Command Prompt. This will put you on a command line in the WinRE.
  6. Enter "regedit" without the quotes.
  7. Highlight HKEY_LOCAL_MACHINE (HKLM) in the left pane.
  8. Go to the File menu and choose Load Hive.
  9. In the source box, navigate to the drive where Vista is installed (C: in my case). Drill down to C:\Windows\System32\Config. Choose the "System" file (with no extension). Hit OK.
  10. In the next window name the hive "Broken System" without the quotes.
  11. Hit the plus next to HKLM. You will see a key named " Broken System".
  12. Drill down to HKLM\Broken System\ControlSet001\Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318}.
  13. Look in the right pane for an Upper Filters line. If you see "snapman" without the quotes, you need to delete it. 
      
  14. Only delete snapman by using the Modify on the Edit menu entry. Make sure you do not delete any other Upper Filters in the list.
  15. You should also check HKLM\Remote System\ControlSet001\Control\Class\{71A27CDD-812A-11D0-BEC7-08002BE2092F} for Upper Filter entries. If you see "snapman" remove it from there as well.
  16. Now unload the Remote System hive. Highlight it in the left pane. Go to the File menu and choose Unload Hive. This will save the changes in the Vista registry.
  17. Exit the command prompt and hit Restart
  18. Keep your fingers crossed…

In my case this solved my problem and I was finally able to boot Vista without having to resort to a rebuild. Your mileage may vary… good luck!!!