Windows Update says there is not enough space

Short answer: Windows Update needs room to download and unpack updates, often 10 to 20 GB for a feature update. Free space with caches, temporary files and old update files first. Do not delete anything inside C:\Windows by hand.

By hand, with Windows' own tools

Run Settings > System > Storage > Cleanup recommendations.
Remove Previous Windows installation(s) if you no longer plan to go back to the old version.
Empty the Recycle Bin and remove old installers from Downloads.
Connect a USB drive: Windows Update can use it for temporary space.

With Sparewise

Warns before Windows Update runs out of room, and says how much more it needs.
Shows Windows leftovers with the Windows tool that removes each one safely.

Questions

How much space does a Windows 11 update need?

Monthly updates need a few GB. A feature update can need 10 to 20 GB free.

Can I delete the SoftwareDistribution folder?

Not by hand while updates run. Use Cleanup recommendations, which removes old update files safely.

Get Sparewise, free

Get it from the Microsoft Store or download the installer

Free · Windows 10 and 11 · No account · No telemetry · Everything it removes can be put back

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