time capsule won't backup in Tahoe!?

tomazo wrote:

after updating to Tahoe, time machine stops backing up my Mac!??? ... nothing about that, just that in macos27 it won't work! ... is there a fix? /update? APPLE! hello this is not ok!

Time Capsule w/ Time Machine...

Apple discontinued the Time Capsule in 2018, Time Capsule is on its way out.

macOS 27 will no longer support Time Capsule disks for Time Machine

Tahoe should still work...

Try a different drive and start a new backup if you have an issue

You do not really provide any more information to address the issue(?)

3-2-1 Backup Strategy: three copies of your data, two different methods, and one offsite.

More than one device, more than one backup methodology.

—Back up your Mac Back up your Mac with Time Machine - Apple Support

In your case, if TM is not backing up to your Time Capsule, the issue is not macOS 26 Tahoe but rather something about your setup. Worth noting that some recent threads have identified using non-ASCII characters in the name of a backup causes problems with Tahoe. If you have accent marks, etc., in your computer name and thus your TM backup name, that may be the issue. Try changing the name.

Bigger picture, if you fix it now it's a temporary solution. Time Capsule uses a deprecated format for networking (AFP), and while that format works with macOS 26 Tahoe, the format will no longer be supported by Apple starting with macOS 27. It has now been over 7 years since the Time Capsule was last sold by Apple, and that means the product is now considered 'obsolete'.

The simplest method to continue using Apple’s Time Machine to back up your Mac(s) is to buy an external drive and connect it to the Mac(s) regularly to back them up (or leave the drive connected to a desktop Mac). External storage is relatively inexpensive, a 1 TB SSD or a 2-4 TB HDD can be purchased for <$100. 

To back up your Macs over WiFi, the most straightforward way is to use a network attached storage (NAS) device – essentially a box for hard disks that connects to your network. Ideally, choose one that offers turnkey support for Time Machine out of the box, both Synology (setup instructions) and QNAP (setup instructions) do so. Technically, you can stand up a Time Machine server in other ways (including using a Mac as a TM server), but an NAS is arguably the most straightforward way to set up network Time Machine backups. 

Personally, I use a Synology DS223j with a pair of 10 TB HDDs installed to back up 5 Macs in the house with Time Machine (separate shared folder for each Mac sized at ~2.5x the internal storage), with the remaining space used as general file storage for everyone in the house.