I just ran the Software Updater (on Ubuntu 16.04). While installing the new packages (including a new kernel version) I got a Grub Secure Boot alert. After that the Software Updater crashed. It stuck at post-installation-triggers on shim-signed.

After having killed all processes related to dpkg I tried to configure it again

sudo dpkg --configure -a

which returned the following:

Setting up shim-signed (1.32~16.04.1+0.9+1474479173.6c180c6-1ubuntu1) ...
debconf: DbDriver "config": /var/cache/debconf/config.dat is locked by another process: Resource temporarily unavailable
dpkg: error processing package shim-signed (--configure): subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:

I fear that if I restart I'll have problems with booting. Can I reconfigure shim-signed, or can I revert the update somehow?


1 Answer 1


Apparently after the command

sudo rm /var/cache/debconf/*.dat

and an overall reconfiguration of dpkg, shim-signed has been fixed. I just booted and everything seems fine...

  • worked for me, thanks! (fixed my apt update, that is, the original problem still exists) Mar 5, 2018 at 23:47

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