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So I've just finished messing up my computer beyond repair. I originally had a Windows 7 install on my 64GB SSD and all my data on my 1.5TB HDD. So I decided to install Windows 8 Consumer Preview. I tried to clone my 64GB SSD onto my HDD; but that didn't work either at first. I later learned that it wiped all my data off of it. Thank goodness for the cloud. So I retried the cloning after I realized that my data was gone, and I finished it. So I rebooted and got a cryptic error message: BOOTMGR is compressed. Press Ctrl+Alt+Del to restart.

So I did. Several times. I followed the instructions to rebuild the bootmanager from many websites, including HowToGeek,, and more. None worked.

BTW, I've lost my Windows 7 Professional DVDs. All I have is my Windows 7 Home Premium DVD. It's the one I got with my laptop.

How can I get back to a working computer? I'm willing to wipe anything, as my data is all in the cloud.

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> So I've just finished messing up my computer beyond repair. Congratulations and welcome to the club. Gooble-gobble, gooble-gobble. You can pick up your membership kit (which contains a logo’d hat, t-shirt, keychain, and frisbee) at the club headquarters. > I later learned that it wiped all my data off of it Ouch! That’s why I don’t trust any software (not even that which I write myself) and always try to do everything—especially potentially destructive actions like partitioning—myself instead of letting installation software do it. – Synetech Jun 4 '12 at 0:46
up vote 9 down vote accepted

First of all: It's a DVD, not a CD. ;)

Second: Your story sounds a bit cloudy. :(


  • Boot from the DVD.

  • Click "Repair your Computer"

  • Select "Restore your computer", and click Next

  • Click "Cancel" on the two screens that pop up

  • Click "Command Prompt"

  • In the command prompt:

    • EDIT: Simply compact /U C:\bootmgr should work. If so, skip the next steps & just reboot!

    • Since BootMgr is hidden, type in Attrib -S -H +R C:\BootMgr and press Enter

    • Assuming there is no error, type in Notepad and press Enter

    • Browse to C:\

    • Select Files of type: Show all files

    • You should see BootMgr in the list. Right-click it, and go to Properties, then Advanced.

    • Unselect "Compress contents to save disk space", and press OK/OK

    • Back in the command prompt, type in Attrib +S +H +R C:\BootMgr

  • Reboot

This will decompress the boot manager, which will hopefully be enough. But if it isn't, you can use the same process to decompress other files/folders.

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Wow! It worked! Thanks a million. – JavaAndCSharp Mar 5 '12 at 11:39
The sheer badassery of this answer deserves so many upvotes. – NReilingh Jun 3 '12 at 3:50
@NReilingh: I'm assuming you got stuck in a similar position. And yes, this answer is pretty badass, seeing as it saved me from several formats, terabytes of data download from the cloud, and two OS reinstalls. – JavaAndCSharp Jun 3 '12 at 22:27
@NReilingh: Haha thanks. xD @JavaAndCSharp: Glad it helped! I just remembered there's an even easier way to do this... a simple compact /U C:\bootmgr would've also solved the problem. :-) I'll update that. – Mehrdad Jun 3 '12 at 22:30

Rebuilding boot manager won't work, since even if you do rebuild it, the compression attributes remain & the bootmanager will get recompressed.

This is what I did when I was in a similar situation:

  • Boot from the Windows 7 DVD (any edition will work).
  • Click 'Repair my Computer'
  • At the prompt to select your OS installation, click the button that says 'Load Drivers'. This should bring up a explorer-style drive browser.
  • Right-click on the drive you tried to compress(most probably the C drive), and deselect 'Compress this Drive', which should still be ticked on. Hit apply, and apply to subfolders/files.
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Hmm. This sounds like it'll work; I'll try it tomorrow morning. – JavaAndCSharp Mar 5 '12 at 4:38
I tried Mehrdad's answer above and it worked. – JavaAndCSharp Mar 5 '12 at 11:41
glad to hear, @JavaAndCSharp – Sathya Mar 5 '12 at 11:42
@Sathya - You mind getting rid of this answer considering Mehrdad's answer worked. – Ramhound Mar 5 '12 at 12:45
@Ramhound I don't see why I need to remove it. It's an alternative, posted before him & will work as well. – Sathya Mar 5 '12 at 13:05
  1. Download Windows 7 Professional ISO from Microsoft.
  2. Make a bootable DVD of Windows 7 And Windows 8.
  3. First install Windows 8.
  4. Partition your HDD to minimum 20GB.
  5. Install Windows 7 from the DVD.
  6. Use the SSD to store files.
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erm... This question was already answered with an answer that was way simpler and easier. What's the point of this one? – JavaAndCSharp Jun 3 '12 at 22:28

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