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Consumer Products => Avast Free Antivirus / Premium Security (legacy Pro Antivirus, Internet Security, Premier) => Rescue Disc => Topic started by: Lisandro on October 08, 2007, 01:27:27 AM

Title: avast CD fails to check a partition
Post by: Lisandro on October 08, 2007, 01:27:27 AM
Three days ago a friend of mine call me to fix his computer.
Windows was not booting at all, after the first options, it keeps on a blank screen.
Safe mode does not work, last known good configurations neither...

So, I've used Bart CD and what was my surprise when I see that it can't use chkdsk (scandisk) in the first partition (system, active, NTFS) saying that the whole partition table was corrupt.
I've tested Acronis Disk Director disk and I could even browse folders and files...

Came back to Bart CD and the same results...

Anyone could guess why can't I use Bart CD with this partition?
Title: Re: avast CD fails to check a partition
Post by: DavidR on October 08, 2007, 01:51:33 AM
If the partition table is corrupt to all intents an purposes it doesn't exist. Is it the partition table or MBR that is the real problem ?

If you can boot to a command prompt, does the partition show then, probably not.

A little google returns many hits, http://www.google.com/search?q=partition+table+corrupt (http://www.google.com/search?q=partition+table+corrupt).
This is just one (its and old topic) but it also mentions trying acronis recovery expert amongst other things. Thought this issue seems different to yours as they could see the files.
Title: Re: avast CD fails to check a partition
Post by: Lisandro on October 08, 2007, 03:14:04 AM
If the partition table is corrupt to all intents an purposes it doesn't exist.
Don't forget that Acronis not only recognize it than browse it... read...

Is it the partition table or MBR that is the real problem ?
BART CD couldn't scan, couldn't verify for errors... the message was about partition table, not MBR.

If you can boot to a command prompt, does the partition show then, probably not.
No, I can't boot on the Console (although it was installed as a boot option).

Which are the limitations of BART CD to read a corrupt partition?
Why does Acronis Disk Director read it?
Title: Re: avast CD fails to check a partition
Post by: DavidR on October 08, 2007, 04:27:56 AM
Sorry misread that I thought it read, Acronis couldn't read rather than could read it.

I also missed out the URL to the topic I mentioned, http://www.wilderssecurity.com/showthread.php?t=54573 (http://www.wilderssecurity.com/showthread.php?t=54573).

Reading some of the links in the google results, some low level utilities like acronis disk director bypass the normal OS boot checks so that may be why it can read the partition where the Bart CD can't. This may be  because the bard cd is effectively loading a cut down version of the windows OS and I can only assume (I have no practical experience of it) that it would use the normal boot methods looking for the partition table information etc.
Title: Re: avast CD fails to check a partition
Post by: Lisandro on October 08, 2007, 05:50:56 PM
Reading some of the links in the google results, some low level utilities like acronis disk director bypass the normal OS boot checks so that may be why it can read the partition where the Bart CD can't.
If this is true, then it's a lack of troubleshooting features of BART CD: it will depend (too much) on the health of the installed Windows.
Can Alwil team drop some lines here?