Comment 2 for bug 576171

Upgrading from 9.10, updated earlier today to latest. This host does not have any non-ubuntu packages installed, as far as I know. Using update manager to update to 10.04. Fails, popupd window reads (partly in Finnish):

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Tarvittavia päivitykseen liittyviä
tarkistuksia ei voitu tehdä

An unresolvable problem occurred while calculating the
upgrade:
Paketti "ubuntu-desktop" on merkitty poistettavaksi, mutta se on poistojen estolistalla.

 This can be caused by:
 * Upgrading to a pre-release version of Ubuntu
 * Running the current pre-release version of Ubuntu
 * Unofficial software packages not provided by Ubuntu

Jos kyse ei ole näistä, ilmoita tämä ohjelmavirhe paketille ”update-manager” ja sisällytä kansion /var/log/dist-upgrade/ tiedostot virheraporttiin.

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Only unusual thing is, I restored the disk from disk image made with Clonezilla 1.2.3-27. Booted up just fine and seems to work OK (except that upgrading to 10.04 fails). Seems unlikely taking and