Have 400Gb free-standing/USB connected external disc.For Full System Backups - 50% free spaceBacked-up yesaterday - slowRan defrag to tidy up disc - after 3% it hungmessage displayed: J:\$BitMap lost - please save file elsewhere. Had no alternative but to down power external disc.Two internal discs were then defraged successfully.Will really appreciate help as to why and what to do to defrag external disc, from aomeone far cleverer than me. If you do reply ... thanks for taking the time to help.2 people need an answerI do too

In article <77f29ecd-1b85-48a9-88cd-944514d369d3@communitybridge.codeplex.com>, jently says...Have 400Gb free-standing/USB connected external disc.For Full System Backups - 50% free spaceBacked-up yesaterday - slowRan defrag to tidy up disc - after 3% it hungmessage displayed:  J:\$BitMap lost - please save file elsewhere.  Had no alternative but to down power external disc.Two internal discs were then defraged successfully.Will really appreciate help as to why and what to do to defrag external disc, from aomeone far cleverer than me.  If you do reply ... thanks for taking the time to help.I am supposing you have tried chkdsk j: ......PoutnikThe best depends on how the best is defined.

Hi Poutnik,Tks for replying. Yes, have run chkdsk J: "No problem found". It's a mystery. Search of computer hasn't found a $BitMap file on any disk and to be honest, I don't know what it is, or what it's for. Defrag prog only seem to hang on J: drive.

In article <b7b950ca-d394-4665-8f08-Email removed for privacy>, jently says...Hi Poutnik,Tks for replying.  Yes, have run chkdsk J:  "No problem found".  It's a mystery.  Search of computer hasn't found a $BitMap file on any disk and to be honest, I don't know what it is, or what it's for.  Defrag prog only seem to hang on J: drive.$Bitmap is a NTFS files discribing alocated clusters on the disk.Each Allocated/free cluster is represented by single 1/0.Essential for NTFS logical disk to work.PoutnikThe best depends on how the best is defined.

In article <b7b950ca-d394-4665-8f08-Email removed for privacy>, jently says...Hi Poutnik,Tks for replying.  Yes, have run chkdsk J:  "No problem found".  It's a mystery.  Search of computer hasn't found a $BitMap file on any disk and to be honest, I don't know what it is, or what it's for.  Defrag prog only seem to hang on J: drive.I guess thes NTFS $xxxxx metafiles are not normally displayed evenif hidden a/o systems files are to be displayed.PoutnikThe best depends on how the best is defined.

Guess you're right, Poutnik. Will get hold of the guy that built my system today - now he's back. Will post again once I've spoken to him. I'm just intrigued to know what's going on.Got an idea that this external disk is heading for the rubbish bin. Seems a better option than having a backup system you can't rely on.

Note that a disk can be OK, but file system management could critically fail.I would format a disk, perform thorough surface check and try to fill it with not critical or redundant data.Check also USB connection, my Vista once periodically reported attaching and detaching the USB disk, until I switched to other plug.

Hi Poutnik,Apologies for the delay in coming back. Thanks for you posting on Sunday - it got my brain in gear!Have now defragged the disk. Being it was a system backup it took forever, but it was successful. Have successfully restored some files to check the validity of the copies. Still can't establish what the missing files are, but everything seems to be running OK.I've learned a severe lesson, and I think my problem has been my own impatience ... because there are no little dots flying into a folder to say the thing is actually doing something, I 'paused' it and stopped it and caused my own problems! I used to accept that the mainframe I managed was just left to it's own devices until it had finished. What gives me the idea a PC should hurry itself up.Thanks for coming in here and giving me the nudge I needed to sort it!Best wishes to you. Jently

In article <08721417-c5c5-4829-b443-865f03f8e323@communitybridge.codeplex.com>, jently says...Thanks for coming in here and giving me the nudge I needed to sort it!Best wishes to you.  JentlyI am glad my notes could by help for you.I am not ore than just experienced user,pleased tobe asupport to anybody.PoutnikThe best depends on how the best is defined.