無法直接更新上11.04 - Linux

用內建的upgrade
好幾次都卡在Setting up new software channels
沒法升級。請問我該怎麼做呢？謝謝

錯誤訊息如下：

Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade:
E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by
held packages.

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

If none of this applies, then please report this bug against the
'update-manager' package and include the files in /var/log/dist-upgrade/ in
the bug report.

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Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

Please report this bug against the 'update-manager' package and include the
following error message:
'E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by
held packages.'




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