WD MyCloud EX2 Ultra not found by Acronis True Image for WD

I've just received my WD MyCloud EX2 Ultra drive and configured it. It shows up on the PC in its own right and as a mapped drive. I have successfully used Windows 7 Backup and Restore to make a backup, so the system is communicating with the drive just fine.

However, Acronis True Image for WD insists there is no drive hooked up to the system and that I have to set up a network connection first. I've gone through all the help articles in WD and after a day and a half am no farther ahead.

I've also tried enabling SMB 1 and disabling McAfee just in case but this has made no difference.

Any thoughts? I'm running Windows 11 and I'm wondering whether that might be part of the issue?