Windows Updates need a lot of disk space, which is a problem on devices with small amounts of internal storage. Microsoft is fixing this by “reserving” some disk space for updates in the next version of Windows 10, codenamed 19H1.
Microsoft has been pushing cheap laptops with small hard drives for years now. But anyone who has ever used one has quickly run into a major issue: They usually don’t have enough storage left over to install major updates. This leaves them without important patches, security fixes, and new features. While you shouldn’t update to the latest version of Windows on the first day, you do want to eventually get there. So this is a serious problem.
Right now, the workaround is to either delete as many files and programs as possible or download the update to external storage. Neither answer is always easy, especially for a college student who has a cheap device, no USB drive, and a need to keep all their files and programs.
Microsoft is trying to address this with a method that is bound to be controversial. Starting in the next major release (and available to Insiders now), Microsoft will reserve at least 7 gigabytes of space on your hard drive.
The space won’t go completely wasted. Windows will store temporary files here when space isn’t needed for updates. Files created by apps and processes that would have taken space anyway will now go into this reserved storage. When it’s time to update, Windows will automatically delete all the files in reserved storage and use the space for downloading update files.
Microsoft says it isn’t using a virtual drive to make this happen. As Microsoft’s Craig Barkhouse explains in the TechNet comments:
Instead we designed an elegant solution that would require new support being added to NTFS. The idea is NTFS provides a mechanism for the servicing stack to specify how much space it needs reserved, say 7GB. Then NTFS reserves that 7GB for servicing usage only. What is the effect of that? Well the visible free space on C: drops by 7GB, which reduces how much space normal applications can use. Servicing can use those 7GB however.
How much space is reserved depends on what optional features and languages you have installed. The more features and languages on the system, the more space will be reserved so that those features can be properly updated as well. If you later uninstall a feature or language, the reserved space will shrink.
Microsoft says reserved storage should start at around 7 gigabytes and go up from there.
In theory this space may have been used anyway and users aren’t losing anything. But some users have less than 7 gigabytes of temporary files at any one time. Those users will see less space available overall. It’s a compromise that will help some people while reducing available storage for others.
Windows 10 19H1 will likely be released in April 2019.