"To choose what voice you hear while using Read Aloud, sign in with your Microsoft account."

I just started having the same issue on my iPhone and Windows PC. I didn't update any of them. I was listening to a Word document on my iPhone when it suddenly stopped and started giving this error. Also, the iPhone voice is so much more annoying than the PC voices.

My experience was the same, only on Windows 11 pro pc, I was listening and it suddenly started giving me errors that I was not signed in. Two hours of troubleshooting with Microsoft level 1. No dice.

Something is stopping Word from using Aria, and incorrectly telling the user that they "To choose what voice to hear while using Read Aloud, sign in with your Microsoft account". This shows that Microsoft did something that makes MY active, current, proper MS login is not recognized when it comes to using Aria in MS Word.

Aria STILL works with Windows Navigator. Just not Word any longer.

I've tried rebooting multiple times. I've tried different new Word docs. I've logged out of my MS 365 account and logged back in. I moved to my laptop and found exactly the same problem there now too.
With Level 1 Microsoft support, we refreshed the MS Office install, we removed and reinstalled all of MS Office, we checked all of the Narrator settings, about two hours of troubleshooting.

Here's my diagnostic criteria.

Windows 11 Pro, fully updated, on Dell XPS 8950 tower.

Microsoft 365 account, current and logged in, Office installed locally.

Windows Narrator, I've downloaded the English (Americal) language pack, and selected "Aria", as shown below. When I turn on Narrator, it in fact DOES use Aria.

When I went into MS Word before, Aria was a choice. I had Aria selected in Word as my voice there. Aria was the high-quality voice I have used every day.

Within Word, select "Review", then "Read Aloud". Sometime today 9-22-2023, it stopped having a healthy connection to Microsoft or something because I get the following popup...

Now when I clear the popup, it instead defaults to a mechanical David voice, and the drop down doesn't offer the choices from the Windows Settings screen I shared above. Note that I AM in fact logged in to my Microsoft account, as shown by my icon and name at the top.

When I go to Settings, Time & Language, Speech, the voices don't show "Aria" as a choice. Further, if I try to "Remove" a voice package with the intent of reinstalling it as a troubleshooting step, the window just freezes and never uninstalls the package.

Something is stopping Word from using Aria, and incorrectly telling the user that they "To choose what voice to hear while using Read Aloud, sign in with your Microsoft account". This shows that Microsoft did something that makes MY active, current, proper MS login is not recognized when it comes to using Aria in MS Word.

Aria STILL works with Windows Navigator. Just not Word any longer.

I've tried rebooting multiple times. I've tried different new Word docs. I've logged out of my MS 365 account and logged back in. I moved to my laptop and found exactly the same problem there now too.
With Level 1 Microsoft support, we refreshed the MS Office install, we removed and reinstalled all of MS Office, we checked all of the Narrator settings, about two hours of troubleshooting.

And... here we go again! Exactly the same problem as in July 2023! :(

I woke up today to find a stream of people commenting on this thread, experiencing this same problem. Dreading when I opened the document. Sure enough... back to robotic voices again. Amazing stuff from Microsoft.