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Today I did my typical "update all" routine when the package manager GUI told me many things needed updating. It chugged along and needed some confirms. I rebooted because one of the upgrades had stripped all the chrome off my windows making them look old-school X. After the reboot I have a red triangle in my system tray telling me my package info is outdated. Odd, since I just ran a big update.

Now if I go to the command prompt and run apt-get update I get the following:

jal@jal:~$ sudo apt-get update
[sudo] password for jal: 
0% [Working]/usr/lib/apt/methods/http: symbol lookup error: /usr/lib/apt/methods/http: undefined symbol: _Z14maybe_add_authR3URISs
E: Method http has died unexpectedly!
E: Sub-process http returned an error code (127)

Throwing a little Google Foo around I came up with this bug report from Dec 2009 on the Debian list. It seems the proposed fix in that bug report is to downgrade to apt-, apt-get update, and upgrade apt again.

I usually just run into things like this without asking for help, but when the package manager is involved I get just a little cautious. I don't really want to blow my packages up or do something ugly to my system.

So in short, how do I downgrade apt without screwing myself in the process?

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up vote 2 down vote accepted

Try this first :

sudo apt-get install --reinstall apt

I tried it myself, no risk to your system.

If it doesn't work, you'll have to get the package from

Choose the good one for your distribution. And install it with dpkg :

sudo dpkg -i apt_#version#.deb

Everything should work fine but I didn't have tested this.

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when I sudo apt-get install --reinstall apt it's responding The following packages cannot be authenticated! which I would not expect from a core package like apt. Is this a clue that something else is hosed? – JD Long Oct 19 '10 at 21:20
Yes. I think you may have a bad repository that have probably upgrade apt and maybe some other packages that shouldn't be upgraded. Check all your third party repository to find the one responsible and all the packages that were upgraded, once you have desactivate the repository and reinstall apt with dpkg you will have to downgrade all of them to be sure that you'll not run into another problems. – Nyamiou The Galeanthrope Oct 19 '10 at 21:30
--reinstall didn't help so I used the dpkg approach and downgraeded to a previous version. I then did an apt-get update and apt-get upgrade and I am golden. I don't know what happened but it's fixed now. Thanks for the fast response! – JD Long Oct 19 '10 at 21:47

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