Time Machine Can Not Backup

Question

At first the error was that the sparsebundle was in use. Manually deleting got it working for a short time, but then I got other, more general errors.  Including ones saying there was no space on the TC, which makes no sense since it's supposed to delete old backups automatically to make space (both my HD and my TC hold 1 TB and the HD is only half full).  Rebooting Apple Time Capsule led to a several days long backup attempt then it failed.  Now it just fails when I try to backup. 
"Backup Failed.  Time Machine couldn't back up to "Cyndi's Time Capsule."
Running Mavericks (10.9.3) on MacBook Pro, connection via ethernet.  TC firmware is 7.6.4 (I updated it as part of my troubleshooting).
I'm assuming I need to do a wipe or reformat of the Time Capsule and start from scratch.  But I want to make sure that one, that's the right thing and two, that I do it correctly.
Any Mavericks-specific advice is welcome.
Thanks,
Cyndi

Answer 1

Mavericks latest update was supposed to fix all these problems.. and pigs might also grow wings and fly.
The TC you have is fairly old.. at least 3years. And maybe up to 6years..
What model is it.. A1xxx from the base??
If it is earlier than Gen3.. ie A1355, my advice is to simply replace it.
For a Gen3 it can be worth the effort to see if it will be reliable but know you are living on borrowed time. This model used a less than super reliable hard disk. And the hardware can just breakdown. So 3years is getting to be end time marker for stuff.
Format the disk may be necessary.. I am not sure.
But you certainly need to do a factory reset.
1.
The Factory Reset universal
Unplug your TC/AE. Hold in reset. and power the TC/AE back on..  all without releasing reset and keep holding in for about 10sec. The time is not important.. it is the front LED rapid flashing that indicates you are in factory mode.
Release reset.
If it doesn’t flash rapidly you have released reset at some point and try again.
Be Gentle! Feel the switch click on. It has a positive feel..  add no more pressure after that.
TC/AE will reboot after a couple of minutes with default factory settings and will wipe out previous configurations.
No files are deleted on the hard disk.. No reset of the TC deletes files.. to do that you use erase from the airport utility.
2. Redo the setup with airport utility.
Give the TC all SMB compatible names.. That simply means names that are short.. no spaces and pure alphanumeric.
eg Your current name fails. "Cyndi's Time Capsule"
It has spaces and an apostrophe.
I recommend a name like TCgen3
For wireless use TCwifi
Anything you like as long as it follow the rules.. short, less than 10 characters is excellent.. make 20 tops. No spaces and purely alphanumeric.
3. Manually mount the TC.
In Finder use Go, Connect to server.
Type in the address.
AFP://TCname.local (Where TC name is the new short name. Local is the default domain and seems to help).
or. Even Better if the TC is setup as main router or with static IP.
AFP://10.0.1.1 (this is the default IP of the TC.. type in its IP address but that means it has to be fixed.)
When you do the above you will be asked for a password.. type that in.. public by default. But the new setup may force you to change it.
Don't forget to save it in your keychain.
4. Make sure ipv6 is set to link-local.
eg for wireless in the network preferences on the computer.
5. You might still need to keep things awake now and then by rebooting the TC.. if Mavericks forgets where the TC lives just pull the power cord.. count to 10 and plug back in. If it happens once a week.. it is merely annoying.. more often than that.. well I would start seeking another backup means altogether.
I also btw think a Gen3 TC or earlier is going to work better on 7.5.2 firmware. If the above happens I would try the downgrade.. easy to do in v6 utility.. simply hold down the option key while clicking version.
You might need to click other to pick up earlier ones.. but 7.6.1 is certainly more stable than 7.6.4