Anyone else found that scheduled Time Machine backups don't ever run since upgrading to 10.11, please?

Manual fine. Plenty of disk space; tried disabling/re-enabling etc.

The Prefs Pane says that the next backup will be an hour from now.

But no backup takes place.

You might wish to check out Time Machine Not Launching Automatically in the Mac OS X System forum.

It might be warranted to run a search (see Search button above) to see if discussion of similar concerns have already hit the forums.

Do you have TM preferences set to Show Time Machine in menu bar? Click that menu bar icon. One option is to back up now. Does the backup start?

Thanks!

Yes, I did search on 'Time Machine' before I posted; but I didn't spot a relevant thread. Sorry :-(

Jon,

Yes under those circumstances the backup always starts.

On scheduled the time of the 'Next Backup' also always advances by one hour when the time arrives.

But no backup takes place.

You are not alone. I have been plagued with that since the first El Capitan beta. I reported it to Apple through the beta test system and they suggested turning off, getting rid of Shockwave and/or Flash — it did not help. I switched the backup drive from a Time Capsule to an attached drive and no help there. I have the same results when logged onto another account so the problem is systematic, but I have yet to figure out what the stopper is.

Thanks, Joe - that's a real help.

Yes, because it tells me with 99.99% certainty that there is nothing wrong with my system -)

Booting every time without the UPS attached isn't really an option since I do like that extra security.

I'll call Apple in the morning (I have AppleCare) and see if they are planning a fix!

Your help appreciated.

UPDATE:

I am running OS X 10.11.2 Beta and with the second update of that version Time Machine began to once again run automatically.

Apparently somewhere in there a fix for the Time Machine problem was included.

Thanks, Joe - this is very good news!

If the Time Machine drive is connected by USB, USB may be the issue. I have an Apple USB keyboard and a USB Apple mouse plugged into the keyboard. After upgrading from Yosemite to El Capitan, the keyboard and mouse would sometimes refuse to power up. This happened when trying to wake the computer from sleep by either pressing a key or clicking the mouse. The only recourse was to force a shutdown and then restart.

I did a lot of troubleshooting, including trying different USB ports on the computer, a different keyboard and mouse combo, and resetting SMC. My wife finally nailed the problem (and she's inordinately proud of this since she's not computer-savvy) by pointing out that I had a powered, 4-port USB Belkin hub plugged into a USB port on the computer. No, I didn't plug the keyboard into it (although I tried that once when the keyboard wouldn't respond) but after disconnecting the hub, the problem never recurred.

My guess is that the USB issue listed by Apple in the 10.11.2 beta will address this. After the final update is available, I'll try the hub again to see what happens.

My Time Machine backup is not affected because it is connected via Thunderbolt, so I have had no issues with it.

Nice try but as I stated previously Apple acknowledged the issue existed and offered possible solutions that proved ineffective. The problem extended across user accounts, several versions of OS X beginning with 10.11 public beta and continuing until the second release of OS SX 10.11.2 beta. During that time the Time Machine drive has variously been a Time Capsule connected via WiFi, an external Firewire enclosure, the same external enclosure connected via USB 3, and for the last few months it is a four drive RAID 5 array using a Thunderbolt connection. It would work when manually initiated and would reliably indicate the scheduled time of the next backup, but those backups never occurred.

Yes, my TM is on a FW bus (and the UPS on USB), although that FW bus - on a 'Late 2014' iMac - is of course connected via a TB<>FW cable/adapter.

Having said that, I have several times experienced the phenomenon whereby attaching a thumb drive via USB has 'provoked' TM into backing up spontaneously!

There is a setting in Time Machine that causes it to automatically start and do a backup when a new drive, even a thumb drive, is connected. You can turn that feature off in Terminal with the following command:

defaults write com.apple.TimeMachine StartOnMount -bool false

Thanks, Joe, Yes!

I don't think it's that, though: I use the thumb drives two or three times a day… synching two machines. Even have them in 'Exclude'.

I'm pretty sure that mounting them did not cause the otherwise dormant automatic/hourly TM backup to run (to the designated Volume, correctly) before this problem surfaced - in 10.11.

I mentioned it because it seemed possibly connected with what some have found to be a (UPS on the) USB bus issue.

There are a handful of useful terminal commands and hidden marker files associated with keeping time machine on a leash. I'd never heard of it "pouncing" on a drive though without a prompt? ("Use xxx as time machine backup?")

The "never present" key is useful to keep a drive you move around a lot from producing TM prompts on new machines if you move it around like I did with my service drive.