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So recently I left my laptop unplugged for a few minutes, and since it has nearly zero battery, it cuts off without any graceful shutdown.

After turning it on, it says (via BIOS) that the clock was reset or something, so I went into the BIOS and set it to the correct time, and merrily booted up.

Filesystem check happened, etc, nothing else seemed to be off. The problem is that updating apt results in all my ppas having invalid signatures, and apt always warning me about unsigned packages when I install them.

I assume this is related to the clock resetting - nothing else seems to be out of place. Is there anyway to reset apt so that it will stop complaining about the signatures?

share|improve this question

Bad sig usually can be fixed by:

sudo apt-get clean
cd /var/lib/apt
sudo mv lists lists.old
sudo mkdir -p lists/partial
sudo apt-get clean
sudo apt-get update
share|improve this answer
Yes, perhaps a little searching would have done me well too:… – Zack Michener Feb 28 '12 at 5:10
I'm not proud I'll take the credit Thanks – Ringtail Feb 28 '12 at 5:16
@ZackMichener Please mark the answer solved if you feel it's right, else you could delete the question if you think its a duplicate of the one you linked to. Thanks :) – Nitin Venkatesh Feb 28 '12 at 6:18

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