When I manually search for updates in any program in Microsoft Office Mondo 2016, I have a window with the 30088-27 error.
Mismatch OS and Office ? Did you recently update to WIndows 11 maybe ? Also keep in mind its a pre-release of Office.
From Google error code 30088-27 will be fixed when Office repair tool replaces all the corrupted system files. Follow the steps below to run repair tool to fix the error. 1-Open Control Panel using Start. 2-Click on Programs and select Programs and Features. 3-Click on the Office product that you want to repair. 4-Click Change. 5-Select Quick Repair and click on Repair. If Quick Repair didn’t fix the error code 30088-27, select Online Repair and click on Repair. Note: If Office Repair did not fix the error, remove and reinstall the Office Suite to fix the error code 30088-27.
How are you uninstalling the office? Use OfficeScrubber tool to do that (I hope you are already using it), clean boot your pc, turn of any and all antivirus, make sure the office iso you are installing from has its integrity intact (try downloading the latest available public iso or the latest using officertool or anyother tool on the forum), install office but do not run it, use kms_vl_all to activate and check again.
As I understand it, they fixed it in build 15414. In my case, the error was no longer displayed. Before checking for updates, I recommend deleting or renaming the Updates folder in the Microsoft Office folder.
I deleted the Updates folder and checked for updates and I still had this problem. I removed Office and reinstalled it with OfficeRTool but it installs a 15407 build (at least in the Beta channel) and I still have this problem. In the Account tab, the update channel setting doesn't appear, so I can't change between the Current Channel (Preview) and the Beta Channel. In Microsoft 365 (even with its license converted to Microsoft Office Mondo 2016 afterwards with OfficeRTool), it appeared. EDIT: I no longer have this 30088-27 error.