I happened upon a hidden file (on my HD) today,
and you'll never guess what its name is :    .TimeMachine.Cookie
Don't know squat about it, but -- on my Mac -- its 16-byte contents exactly match the ".0*" file on the backup disk!!!

So... let's just see how well yours match up:
ls -l /var/db/.TimeMachine.Cookie /Volumes/*/.0*
-r-------- 1 root wheel 16 Dec 31 2007 /Volumes/L_d100g/.001a2b3c4d5e
-r-------- 1 root wheel 16 Dec 31 2007 /var/db/.TimeMachine.Cookie

sudo diff /var/db/.TimeMachine.Cookie /Volumes/*/.0*

Ideally, that last command (diff) should produce no output at all (plus an exit code = 0).
If there is [suitable] output from diff, then perhaps there's still some hope left here.

--

Hoping you did indeed do the "rm -vf /Volumes/MiniMax/.0017f2e00396" as stated above. Else,
if there are two ".0*" items on your backup disk, then diff will complain about an 'extra operand'.

After entering

ls -l /var/db/.TimeMachine.Cookie /Volumes/*/.0*

I get

ls: /var/db/.TimeMachine.Cookie: No such file or directory
-r-------- 1 steven staff 16 29 Oct 18:16 /Volumes/MiniMax/.001b63c053db

After entering

sudo diff /var/db/.TimeMachine.Cookie /Volumes/*/.0*

I get

diff: /var/db/.TimeMachine.Cookie: No such file or directory

Not sure what this means. It doesn't seem to be what you were expecting.

By the way, I did indeed run

"rm -vf /Volumes/MiniMax/.0017f2e00396" and restarted.

Just a thought: Did you type those things or did you paste them? Pasting is more reliable because you'll avoid typos. It's not always obvious, for example, where spaces occur.

They were all pasted directly from Hal's posts.

Alllllll-righty then.

Try a:
ls -l /var/db/.Time*
[just to see if a hidden file named ".TimeMachine.Results.plist" shows up.]

If you want to skip ahead... my next suggestion will be to create the missing file:
sudo cp -v /Volumes/MiniMax/.001b63c053db /var/db/.TimeMachine.Cookie

When that succeeds, redo the ls and diff from before... and post all text.
Restart and test. (breathing optional)

The problem is solved! Time Machine is now working correctly. No more "can't find backup volume" messages.

I had a problem updating a program today and had to force the computer to shut down. When I restarted I had the 'can't log on' problem, which seems only to be fixed by a system reinstall.

Anyway, I reinstalled the system using Archive and Install. As soon as I had finished reinstalling I tested Time Machine and as on previous occasions it began working. So when moving back the user files I made sure I didn't override anything already there. It meant I had to reconfigure a whole lot of stuff (and am still waiting for replacement codes for some programs that can't use the old codes) but TM is working!

The unfortunate part is I still don't know exactly what caused it to stop working. We do have a solution, however, albeit a rather drastic one.

Many thanks to Hal for sticking with this. I really appreciate it.

Talk about anticlimactic.

Are you saying you had to do the whole reinstall business *before*
getting an opportunity to test out the cp command's effectiveness?

I never got to do the cp command.

I got the log-in-loop syndrome which meant (as far as I know) I had nowhere to go except to reinstall the system using archive and install, which at least preserved my files, etc.

This log-in-loop, where the computer will not accept the password, happened to me a lot when I first installed Leopard, but it hasn't happened for a long time. I was updating Parallels Desktop when the computer froze and I had to (as I thought) force shut down the computer.

Reinstalling the system is certainly not my preferred solution to any problem! It takes several hours to get everything back to how it should be (unless of course you have a TM backup, then it only takes maybe an hour or two!).

The fact that the required cookie couldn't be found previously, however, makes me think that creating it may well have been the solution. Hmm.

Sorry about the anticlimax. Things were actually fairly climactic here yesterday.

Greetings.

I come bearing a gift, in the form of a climax.

I had the same problem. Thanks to this thread I discovered that my /var/db/.TimeMachine.Cookie was empty (size 0). Sudocopying the cookie from my network volume, overwriting this file, solved the problem. I suspect this failure occurred after my logic board was replaced.

Thanks Hal!

Welcome to the MacFixIt forums!!!