-643 errors with client backups

[rfajman]

Recently I've started getting -643 errors with my client (at the moment I have only one).  They happen consistently with every backup to every one of my 4 local hard disk backup sets, but never with my cloud backup sets, but only the client backups, not the backups of the server PC itself.  The local backup sets do get many more files (system and program files, as well as user files) than the cloud backup sets (user files only).  I just installed 17.5, which made no difference.  I'm not sure if there is a correlation with the upgrade to 17.0 or not.  I've tried doing CHKDSK on the disks being backed up (no errors), rebuilding some catalog files, and, in one case, resetting the backup set, none of which made a difference.  I'm using Windows 10 Pro v2004 on both the server and client.

Here are the error messages:

+    Normal backup using Backup LG Gram 17 to Backup Set 1 at 9/30/2020 6:33 PM (Execution unit 1)
        9/30/2020 6:33:30 PM: Finished scanning backup set data files
    To Backup Set Backup Set 1...

-    9/30/2020 6:33:29 PM: Copying Programs Disk (C:) on LGGram17
    Scanning incomplete, error -643 (not a chunk file or badly damaged)
        [*] lvtrScanBad: @ fileCount=393,563 folderCount=92,482 treeMemSize=137,326,204 normSpaceCount=2 spanSpaceCount=0 dirMemSize=25,333,308
-    9/30/2020 6:36:59 PM: Copying Data Disk (D:) on LGGram17
    Scanning incomplete, error -643 (not a chunk file or badly damaged)
        [*] lvtrScanBad: @ fileCount=1,607,505 folderCount=40,915 treeMemSize=491,855,520 normSpaceCount=2 spanSpaceCount=0 dirMemSize=14,457,360        9/30/2020 6:45:26 PM: Compressing catalog file
    9/30/2020 6:45:26 PM: Execution incomplete
    Total duration: 00:11:56 (00:11:55 idle/loading/preparing)

Any thoughts?

 

[Nigel Smith]

CHKDSK with what flags? And you may get better results using a less... rudimentary tool. Most drive manufacturers offer better eg SeaTools for Seagate disks.

I'd also try using the same filter as you use for the cloud backups, then slowly expanding it to include other files -- if you can find the problem file(s) you can get as good a backup as you can before things become terminal.

[DavidHertzberg]

rfajman,

It's time you learned how to use the Retrospect Knowledge Base.  Navigate your web browser to www.retrospect.com/support, click the "Knowledge Base" icon, and do a search on "-643" (without the double quotes). 

You'll find this 2017 article, which says "If the Retrospect process ends unexpectedly, it could result in problems saving some of temporary data files that are used when negotiating security with your servers".  It looks as if its solution may solve your problem.  OTOH that doesn't explain why you get no error with cloud backups; Nigel Smith's suggestion might help to provide that explanation—which may have to do with temporary files that aren't used for your cloud backups because they're scanning fewer source directories (how's that for a SWAG? 🤣 ).

As for the CHKDSK flags asked about by Nigel Smith, here's a Lifewire article explaining them.  I found that by Googling "chkdsk windows 10 commands"(without the double quotes).  However the KB article linked-to in the preceding paragraph says the problem is likely to be with Retrospect temporary files on the "backup server", not with the disks being backed up.