Update error code 30088-27 Office 2021 what to do to get corrected????

For what it's worth I have the same problem on 1 out of 3 PC's, from oldest to newest. Oldest is running windows 10 and Office Professional Plus 2016, retail version. Not having issues with that PC, updates Okay. Next PC is Windows 11 PC running Office Professional Plus 2019, retail version. Again no problem updating. Newest PC is Windows 11 PC running Office Professional 2021, retail version. On this one I'm getting the same Update Error Code:30088-27. All Apps on all three PC show version 2046 build 17726.20078. I just updated/tried updating all 3 PCs two days ago. Only 2021 version fails. One thing I did notice, on both older PC, I'm running 32 bit version of Office. On Newest one that's failing I'm running 64 bit version. Don't know if that means anything, but worth mentioning. Tried running online repair, Didn't help.

Today's Bleeping Computer has an article on this problem.

1. Disable Microsoft Office Updates (File/Account/Update Options and select the Disable Updates option)
2. Open an administrative command prompt and then enter the following command:
   "C:\Program Files\Common Files\microsoft shared\ClickToRun\OfficeC2RClient.exe" /update user updatetoversion=16.0.17726.20160

An Office update window appears, let it end, close it and that's all.
If you want you can enable the Updates option again but at the moment it's still not working from there.

Until Microsoft fixes it, when you know the build number of the next update, just run the above command with the new build number and you can always update Microsoft Office simply and easily.

Don't go back to a previous version as someone (from Microsoft as well) is saying, don't you think about the security vulnerabilities that doing this will become exploitable again?
I prefer getting the very latest version then wait for a fix by Microsoft.
The latest version at the moment is: 16.0.17726.20160, this post refers to this version. If and when a newer version comes out and if they still haven't fixed this bug, just run the command above replacing the build number with the latest build number you can get from the page containing the Office version builds.

For what it's worth I have the same problem on 1 out of 3 PC's, from oldest to newest. Oldest is running windows 10 and Office Professional Plus 2016, retail version. Not having issues with that PC, updates Okay. Next PC is Windows 11 PC running Office Professional Plus 2019, retail version. Again no problem updating. Newest PC is Windows 11 PC running Office Professional 2021, retail version. On this one I'm getting the same Update Error Code:30088-27. All Apps on all three PC show version 2046 build 17726.20078. I just updated/tried updating all 3 PCs two days ago. Only 2021 version fails. One thing I did notice, on both older PC, I'm running 32 bit version of Office. On Newest one that's failing I'm running 64 bit version. Don't know if that means anything, but worth mentioning. Tried running online repair, Didn't help.

All of my machines are running the latest version of Windows 11 Pro. Two are running the retail version of Office Home and Business 2019 and one is running the OEM version that came with it from Dell. All are running the 64 bit. The oldest machine is the one that is having the problems, but it is the most capable and fastest machine otherwise. I was able to update Office on that machine by utilizing the Online Repair through the Windows Settings - Apps - Installed Apps. As noted earlier though, all three machines are showing the current version on the Office Account - About Outlook (or Word or Excel), but they all show the older version if you click the About button. Haven't figured that one out yet.

but they all show the older version if you click the About button. Haven't figured that one out yet.

It's not the older version. It's always been like this, the single apps show an older version number than the number shown without clicking any button. That's not a problem. Sometimes the two numbers (Single App number and Suite number) were the same but it was a rare thing.