Windows installation errors

An installer failed and gave you a number. These pages say what each code actually means, and list the fixes in order of how often each one turns out to be the answer.

We cover installation and file errors, because that is what this site is about. For anything else Windows throws at you, this is not the right place and we would rather say so than pad the list.

The step almost nobody takes

Before debugging an installer, confirm the installer is intact. A truncated or modified download produces errors that look like configuration problems and waste hours. Check the file's SHA-256 against our index first: it takes seconds and rules out an entire category of cause.