The patch download fails for Microsoft Office applications, such as Microsoft 365, Office 2021, Office 2019, etc. with the following error codes:
The possible reasons of this issue could be:
To resolve the issues, follow these steps:
Allowlist the mentioned domains in this page in your proxy to download the Office patches.
If the download fails even when the above-mentioned links are whitelisted, follow the steps mentioned below to ensure that there is no network issue or privilege issue in your environment:
Copy the XML content mentioned below and save it with the file name as download.xml. Place the file in the o365 folder that you created in the first step.
<Configuration>
<Add OfficeClientEdition="64" Channel="Current">
<Product ID="O365ProPlusRetail">
<Language ID="en-us"/>
</Product>
</Add>
<Display AcceptEULA="TRUE"/>
</Configuration>
Run Command Prompt as administrator and execute the below-mentioned commands:
setup.exe /download download.xml
echo %errorlevel%
Once the above-mentioned steps have been performed and if the exit code is 0, then there might be a privilege issue in your environment. To resolve, perform the following steps:

In case the problem persists, kindly contact support.