Message "Backup disk identification has changed since the last copy"

Question

Hello!
I have MD033 Time Capsule and my iMac 2012 and MacBook Pro connected to it. Time Machine is set to backup @ this disk.
Every once in a while I get the message you see in attach on my machines. Approximately it means "Your backup disk identificator has changed since the last backup (Possible reason the disk was changed or erased since the last backup or someone is trying to make you make aт illegal backup not on your disk "
I get this message from time to time both on iMac and MacBook but not simulateoneously. Once in a week or a month.
I already reinstalled anew systems on my machines and even replaced time capsule itself to the same model (absolutely new, factory sealed), not even mentioning formatting its disk a dozen times and resetting TC.
Does someone have same problem? Russian support couldn't help and directs me to a repair. But I really doubt that BOTH MacBook Pro and iMac have EXACTLY the same problem with TC. Everything seems as it is a software problem with some of the program

Answer 1

frood42frood42 wrote:
today, my MacBook shows a Message "The identity of the backup disk has changed since the previous backup."
Welcome to Apple's discussion groups.
It may not show anything useful, but try this: Disconnect all external and network volumes. In the Finder invoke the menu option Go > Go to Folder. In the resulting field type "/Volumes" (without the quotes) and click "Go". In the resulting window you should only see entries for any internal volumes. If you see anything else, particularly an item with the same name as your Time Machine volume, you may have the problem described in this article:
http://db.tidbits.com/article/9620
You should trash any such things. The way to prevent this in the future is to prevent any process from running that would write to external volumes that aren't mounted. For Time Machine, turn it off, then when you want to back up, mount the Time Machine volume and choose "Back Up Now" from the Time Machine menu item.