Backup Corrupted?
I have just replaced my PC by new (identical) unit. Before doing so I created a complete backup file and validated it.
Now, on the new PC, I am trying to access a specific data file and get the message "Make sure location is accessible & contains all versions of the backup. May also be corrupted". I have successfully re-validated it and still it is inaccessible. This is a serious result as I badly need access to this data and it leads me to ask what is the point of validation? Indeed, the whole purpose of 'backup' falls into doubt.
Incidentally, other files on other backups created by on the old PC can be accessed.
Thanks. The backup is located on an external 2T hard disc. When created it appeared to validate OK as indeed it did when validation was repeated with the new PC.
It was only when I tried to extract specific data files that 'corrupted' appeared; there was no other useful comment.
Is it a USB drive? Don't connect via a hub, a port in a monitor, a USB extension cord, etc. Connect the external drive directly to a USB port on the rear of the computer case.
Run chkdsk /r on that drive.
Also run a drive checking utility from the drive manufacturer, as those sometimes catch errors missed by chkdsk.
I don't know what might cause this assuming that absolutely nothing else has changed i.e. the drive is connected to the same port, with the same cable, and some backups are useable while this critical one is not.
Your problem does point-out the need to have multiple backups, preferably in multiple locations, for data that is critical to your operation. I'm a little paranoid myself, having suffered computer failures in the past, and so have my data backed to 4 different locations/devices (two of which are daily backups, a third weekly, and the fourth is a monthly backup--all four are on different media in separate physical locations including a separate building and a fire safe).
The hard disc is connected directly to a USB port on the PC. I don't think the problem is one of connectivity, since I am able to access other TI backups on the same disc made both before and after the change of PC without difficulty. It seems to be specific to this one backup (of course, the one I really need!), although I do wonder if the the fact that it includes 20-30 incremental backups is significant, even though validation included the total backup.
I do understand your point and the need for caution. However, what really upsets me is that, having religiously validated the backup (repeated again recently), I am still denied access to files.
What is the point of validation if it offers no protection and doesn't reveal 'corruption'?
John,
Try validating from the TI Recovery CD.
Also try validating each individual backup starting with the most recent and working backwards. Perhaps you many find that you can validate from a certain specific point backwards so that only the most recent part is a problem.
I do understand your point and the need for caution. However, what really upsets me is that, having religiously validated the backup (repeated again recently), I am still denied access to files.
What is the point of validation if it offers no protection and doesn't reveal 'corruption'?
A report of "validated" is only at that point in time. Any file on any disk can develop errors due to disk problems. The fact that the file was good one minute prior to the disk error is irrelevant. Stuff happens.
Try Grover's suggestion. It could well be that one of the older incrementals in that long chain has developed the error, rather than the latest one. But, if any incremental in a chain has errors, all subsequent incrementals would be unrecoverable.
For an Incremental task, after the first full backup, subsequent backups will be incremental, each one based on changes since the previous Incremental backup, all the way back to the second backup being incremental based on changes since the full backup. As such, you need all links in the chain, all incremental backups right back to and including the first full backup, in order to Restore.
For a Differential task, after the first full backup, subsequent backups will be differential, each one based on changes since the first full backup. To restore, you would need just any Differential and the Full backup on which it is based.
You should not allow an incremental chain to become too long. An incremental restore depends upon every incremental in the chain being valid, including the original full. It's better to limit each chain to just a few incrementals, followed by a fresh full backup to start a new chain.
I do understand your point and the need for caution. However, what really upsets me is that, having religiously validated the backup (repeated again recently), I am still denied access to files.
What is the point of validation if it offers no protection and doesn't reveal 'corruption'?
Of course--it's frustrating. I don't know why your backup validates yet Acronis finds it to be corrupt. You should consider opening a support ticket with them.
In the meantime I would try copying your backup-in-its-entirety-of-course to (preferably) another drive internal to your PC and try accessing it again. Just to eliminate the possibility of glitches across the wires. I have had enough trouble with cables and with docking stations for example that I've bought more robust USB cables, and try to connect these directly to the PC's motherboard, a back connection rather than a front port which has tiny wires extending-back into the case and attaching to the mobo.
Not sayin' that's your problem, just trying to help...
P.S. I suppose there is a remote possibility too that explorer has trouble copying your files (it's not supposed to!). On my PCs I use TeraCopy (free) which tends to be faster, has nice features re: Overwrite Older? etc., and might be more robust in checking that files are transferred accurately.
I'm getting exactly the same error when trying to validate or recover files from some backups but when booting the rescue CD , as GroverH has suggested, everything works just fine. If you haven't yet created the rescue CD you can download it from the Acronis site. This is hopefully your salvation.
Validation is memory intensive and puts strain on the hardware. Here are some links on troublshooting corrup archives.
http://kb.acronis.com/system/files/content/2005/12/1517/png_1.htm
Hi grover i just wonder why CD worked and not original method used by the forum member who posted issue? Any idea just for my curiosity.
Sunado, in such a case it's possible that Windows is interfering with the process in some way, which could explain why bootable Rescue Media performs the task much faster than the Windows app.
As for the original poster, we don't yet know, and he has not yet indicated that he ran the two tests I recommended.
thank u tittle...i think that's why its recommended that best option is both to back and restore from CD and not from within windows because then windows cannot interfere and also it will be fast...(also i believe how window interferes would be also beyond comprehension)
Hi grover i just wonder why CD worked and not original method used by the forum member who posted issue? Any idea just for my curiosity.
One difference is that the CD is Linux based, therefore, the memory addressing system would differ. In performing a validation inside Windows, all available memory is used plus there could be memory addressing errors overlap--but that is only a guess.
One of the first steps in addressing a validation issue would be to run memcheck and let it run all night or for an extended period of time. Sometimes, you may have to pull the mem sticks so only one stick at a time is checked. It can be a real pain but often times does pay dividends in finding a bad memory module--if one bad exists.
As the prime vehicle for the restore is the Recovery CD, whether the validation is successful or not as determined by the CD is the most important check.
One of the first steps in addressing a validation issue would be to run memcheck and let it run all night or for an extended period of time. Sometimes, you may have to pull the mem sticks so only one stick at a time is checked. It can be a real pain but often times does pay dividends in finding a bad memory module--if one bad exists.
But how frequently the test should be run...every two weeks or every month etc. any guidelines for newbies like me...also if any error comes up would that mean that RAM is bad and better be replaced?
Memtest isn't something you need to do every month, but certainly should be performed when you suspect that there could be a hardware issue.
In my experience, validation issues are more often caused by disk issues or connection issues rather than memory issues. So, running the disk checks I suggested is mandatory, as well as testing with different connections.
thank u