chkdsk - "An unspecified error occurred <6672732e637878>"

I started a chkdsk on a Win7 64bit computer that got stuck at startup repair. Before that though, I was looking around, the damage seems to be the windows files got messed up after an update. My computer data was intact when I looked around booted through a recovery cd and I checked again via a ubuntu live cd. My question is that the chkdsk d: /f apparently stopped in the middle and gave the following message:

An unspecified error occurred <6672732e637878>
Failed to transfer logged messages to the event log with status 50

What does that mean? Is it terrible? I just restarted the chkdsk anyway and as of now, it is finding less unreadable segments, but is there a risk of data loss?

2nd chkdsk failed

An unspecified error occurred <6672732e637878 41a>
Failed to transfer logged messages to the event log with status 50

Help? What do I do?

Have you figured it out that how can it be rectified?
I am facing the same problem on my external WD Hard disk (931 GB) (it got corrupted while creating Windows Backup).
CHKDSK fails while scanning unindexed files for reconnecting them to their original directory.
I have tried chkdsk /f d: and chkdsk /r /f d: but both fail at this point.

Please help.

Run cmd where you start chkdsk as admin. The error () is a failure to write to system log due to lack of privileges.

I came across a similar problem while running chkdsk as an administrator.
6672732e637878 17ed
But mine said "The disk does not have enough space to replace bad clusters detected in file 1F6A0 of name .
An unspecified error occurred (6e746673686b2e b1f)
An unspecified error occurred (6e746673686b2e 1713)"

Then the computer typed by itself \\ enter three times then \\~ enter

I was working on drive c from drive e and kat ime this error occurred it was then telling me that c drive and e drive had vanished so I typed the directions command to see if it could still read the drive I was in but the system could not find the specified path.