Questions about Wubi, a way to dual boot Ubuntu and Windows without partitioning. However, it's been abandoned for years and is depreciated.

Wubi is an installer for Windows users that allows Ubuntu to be installed and uninstalled in a safe, easy way as with any other Windows application.

Wubi used to be officially supported by Canonical, but it wasn't actively maintained and didn't work on newer Windows computers that use UEFI to boot i.e. all newer computers with Windows 8 and Windows 10 that come with Secure Boot. For this reason, Wubi support was dropped by Canonical and Wubi.exe was no longer shipped from release 15.04. Technically it is still available on some long term releases, but these versions don't work anymore without manual workarounds.

Since then a community-supported fork of Wubi has been maintained that does work with UEFI and Secure Boot. The latest release is available on Github. For more information refer to the Wiki.

With Wubi, Ubuntu is installed onto a virtual disk which eliminates the requirement to repartition (required for a traditional dual-boot) or replace the Windows Bootloader. On older (non-UEFI systems) Wubi boots via the Windows Boot Manager, using a combination of GRUB4DOS (wubildr.mbr) and Grub2 (wubildr), which 'loop-mounts' the virtual disk in order to boot from it.

Notable limitations include a lack of hibernation support, a somewhat less robust filesystem (avoid hard reboots), and reliance on the Windows "parent" filesystem -- therefore, if Windows crashes, it's necessary to reboot into Windows first to have it repair the Windows filesystem before the Ubuntu filesystem. Note: it is not advisable to store important data in a Wubi install unless you also maintain current backups, because Windows' chkdsk will sometimes remove the virtual disk if it believes it is corrupted.

The minimum requirement to run Wubi is 512MB of RAM and about 6GB of disk space (Edubuntu requires about 13GB).

For more information, please refer to the Wubi Guide.

The most frequent questions are: