We had an issue where one of our development servers wouldn’t apply the latest Windows Cumulative Update package and gave the error
0x800f0905
Several typical fixes were tried to resolve including system file scan (sfc) and dism to clean up the image. Both were OK and didn’t report any issues.
The software distribution folder was cleaned and retried with same message.
The update was manually downloaded and applied but with same error.
Solution
Run powershell as administrator
dism /online /get-packages /format:tableWill show all the packages installed. Look for those that start with
Microsoft-Windows-Server-LanguagePack
------------------------------------------------------------------
Package Identity | State | Release Type | Install Time
------------------------------------------------------------------
...
...
Microsoft-Windows-Server-LanguagePack-Package~31bf3856ad364e35~amd64~en-US~10.0.20348.2582 | Installed | Language Pack | 26/07/2024 10:59
....
It should have packages for US english(EN-US) and the regional settings – in our case UK english (EN-GB). If there are any others remove them with
dism /online /remove-package /packagename:<insert package name here>
It may be that EN-US is installed but not EN-UK. If the regional settings are set to EN-UK then windows will try to patch the language pack but it is missing and hence fails. So install the language pack as follows
fix
– run language settings (search for it)
– If English United Kingdom pack is not installed download from this same screen. (click it, then options and download)
– In the language screen set display language to be English-United Kingdom. It will ask to logout (OK)
– reboot
– Login again and update worked.
Conclusion
Make sure you have the language packs installed for any regional settings used. Oddly in this case it seemed to have a mix of US English with UK regional settings but missing the UK language pack. We have other Windows 2022 setup the same way but the language pack was already there!
Even more odd is that the CU updates worked fine prior to this particular release in July 2024!
