USB disks not discovered after OS5 upgrade

I have not been able to do any USB external disk backups from my EX 4100 since I upgraded to OS 5 several months ago. The external usb disks just do not appear in the usb list in the web interface. Therefore a back up job can not be created.

The EX4100 has been working well since i bought it, just one firmware update has given issues during the years. But now I wonder if I have to start looking for something else. Backups are critical.

Do anyone have a good idea what to do? Can the UPS connected have something to do with this?

Please ensure that your My Cloud EX4100 is using 5.14.105 which is the latest firmware and USB Backup app v1.27

The update to the latest Back up app helped, after a reboot the EX 4100 found the attached UPS and also the external WD 2 TB usb disk.

Thank you for the help, now there is a very long lasting back up ongoing…