OSStatus error 2

This error typically relates to user permissions, specifically not have the correct ones to access the Time Capsule. One quick test is to log on to your Mac with an Administrator account, and then, attempt a Time Machine backup. If it works, then you verified a permissions issue with your user account.

Some additional help may be found in this Pondini article.

Try this: Open AirPort Utility on the Mac, see any yellow or red 'flags' associated with the Time Capsule?

OK, let's try this: Click on the Time Machine icon (upper menu bar), then Open Time Machine Preferences.

1. How many drives are listed? If more than one, please describe.
2. If only one drive listed, is it the Time Capsule drive?
3. If yes to #2 above, Remove the TC drive, then Add it back in.
4. Then start a Back Up Now.

Note: In order to perform the Remove and Add functions, the Preferences window must be unlocked. You can do that by clicking on the Padlock image, lower left corner of the Preferences window.

OK, some screen shots would really help.

1. If you would, pls open AirPort Utility and post a screen shot (SS) of your all network devices. MIne looks like this:
2. Then, click on your Time Machine, then Edit within the pop-up window, and go to the Disk Tab. Post a SS of that. Mine looks like this:
3. Then open Time Machine and post a SS of that window. MIne is:
4. And finally, click on Add or Remove Backup Disk above, posting a SS of that. Again, mine looks like:

Very interesting, and puzzling. As mentioned above in an earlier post, it is likely you have a permission problem. But where does it originate from? That is the question.

1. Are you logged in as a User with Admin privileges?
2. Your TC disk is now labeled "Data". Was that always the name? Or did the original name somehow get change to "Data"?
3. The last two screenshots above are puzzling in that Time Machine is prompting you to configure a TC disk for backups. Suggesting TM has lost its way, forgetting that you had it configured previously. What happens when you select the other Time Capsule listed, "Otra AirPort Time Capsule"?

I experience exactly the same issues. How can this be solved?

Stick around....we're trying to come up with a solution. Actually more like, we are trying to define the root cause of the problem.

Congratulations...and I agree, don't mess with success/change anything.