Strange problem with Time Machine - Help!

I have a MacBook Pro running Snow Leopard (latest version) on a 320 GB drive. I have been using Time Machine to back up to a 500 GB external USB drive (Western Digital MyBook).

I never had serious need of Time Machine, only occasion accidental deletions and over-writings, and I never had problems before.

However, today, I was playing Minecraft and I wanted to go back to yesterday's saved game because I died. You have to know that Minecraft only makes a single save to keep the gameplay realistic, so it keeps overwriting the save files. That way, the only easy way to revert to an older game is to make a copy of the save, or just rely on Time Machine. When I entered Time Machine and scrolled back to "Yesterday", I noticed that the saves were from something like 1 month ago. There was nothing in there from yesterday.

This shocked me, not because I'm such a Minecraft maniac, but because I thought "then what else isn't getting saved?". I quickly went to my Photos folder and sure enough, it didn't have a backup of the latest album (which was created 1 week ago).

It's as if it simply stopped backing up.

Time Machine is ON, there are no exceptions set up, there is enough free space on it to keep more than my entire system backed up at least once, and I didn't change any of the settings lately. It's also backing up hourly as it should, I can hear the hard drive spin up and the Time Machine icon is animating. It even says "Last Backup: Today, 22:20" right now, meaning that it made a backup an hour ago. However, the files that were there an hour ago are nowhere to be found in Time Machine.

Can anyone help with this? What could be going on? I've always had trouble understanding Time Machine, but this is clearly a problem and not just me not understanding it.

What I never get is this for example: "Time Machine Keeps Daily Backups for the Past Month": what does this mean? After a month, which daily backup does it keep? Does it consolidate 30 backups into one? How does it decide which files to keep and which ones not to after a month? How do I know what isn't getting backed up?

I really feel like I should not be using Time Machine anymore as it can't seem to be trusted, what should I do?

Thank you for your help!

 

I tried from the Time Machine interface, wasn't there, and then I tried going to Finder and checking out the various folders on the Time Machine disk, wasn't there either. The weird thing is most things are there, but this isn't.

The files are in User/Library/Application Support/Minecraft/Saves

And my Photos folder is User/Pictures/Photos/<one folder for each album>

I noticed that nothing really got saved for the past few weeks or so, even though Time Machine does at least pretend to back things up hourly.

What do you mean by "mounting the sparsebundle"? What is that and how do I do it?

Should I wipe my backup drive and re-start a fresh Time Machine?

 

Thanks for your help!

I sleep my machine many times a day, but I reboot at least once a week... This is the way it was for the past 3 years and there were no problems...

I'll try a repair on the backup disk, hopefully it will say something useful!

 

I did what you said, it doesn't show anything that would look like an error. This is exactly what it says:

• Starting standard backup
• Backing up to: /Volumes/Backup/Backups.backupdb
• No pre-backup thinning needed: 701.4 MB requested (including padding), 14.83 GB available
• Copied 10 files (93 bytes) from volume Macintosh HD.
• Starting post-backup thinning
• No post-back up thinning needed: no expired backups exist
• Backup completed successfully.

I have rebooted since last time and nothing changed.

EDIT:

I created a 60 MB file on the Desktop and hit "Backup Now" to see what the log says. It says exactly the same thing! Including "Copied 10 files (93 bytes) from volume Macintosh HD"! Why 10 files? Why only 93 bytes? It clearly didn't back up my new 60 MB file did it?​

/EDIT

Here's a screenshot and some explanations of my problem:


* the .jpg file has been on my Desktop for more than a month, that one has been backed up, so the problem started somewhere between now and a month ago.

I have many files that I created in the past week, however, none of them show up when I go back as little as one hour in Time Machine. If those files get deleted, they're gone forever, as Time Machine didn't even back them up.

The weird thing is I get no errors whatsoever, and I can see and hear a backup happening every hour, and Time Machine even says "Backing up" and "Last Backup: <time>" with the time being no older than an hour ago.

What I have noticed lately is that backups are incredibly fast. Maybe that might be related to the problem.

Should I just wipe my entire Time Machine disk and restart Time Machine from scratch? Deleting the backup is better than deleting data that isn't backed up...

 

(New post, because otherwise it would get really messy)

Okay, so I checked a few things, none of them worked:

• Deleted "Macintosh HD/Library/Preferences/com.apple.TimeMachine.plist"
• Verified the Time Machine disk - everything seems fine
• Placed a file into the topmost level (Macintosh HD) to see if it gets backed up - no, it doesn't

I have read and tried everything on the following site:
http://web.me.com/pondini/Time_Machine/D5.html

... and I found a thread about a guy who had a corrupted Home folder:
https://discussions.apple.com/message/10267660?messageID=10267660

However, if I had a corrupted Home folder, the topmost level (Macintosh HD) would still get backed up, wouldn't it? Because for me, it didn't.

 

You mean re-format my internal HDD or just the Time Machine one? I think I'll just do the Time Machine first, and if that doesn't work, I won't have a backup, so I can't reformat my internal anyway...

 

Yes, don't worry, I wasn't going to touch my internal drive
I won't have enough space to rename my Time Machine backup and let it start a new one, as the drive is full (but that isn't the cause of my problem, as Time Machine is supposed to fill up the drive, and then delete older backups).

I think I'll just format the Time Machine drive, and that's all I can do now.

EDIT:
I formatted my Time Machine drive and it seems to be working perfectly fine now! The initial backup went fine and the hourly ones seem to work too. Thanks for your help!