An administrator user account became standard and we could not do anything but reinstall

[Ashok Patil]

I suddenly found that sudo passwords are not being accepted, looking at user account revealed that the only admin account became the member of "standard" users, and we could not even create a new user nor change any settings.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: ubiquity 2.8.7
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic x86_64
ApportVersion: 1.23-0ubuntu3
Architecture: amd64
CasperVersion: 1.287
Date: Fri Oct 28 10:40:17 2011
LiveMediaBuild: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[dino99 (9d9)]

This version has expired for some time