I'm also running into this issue on 18.04 (fresh install about 3 months ago)
Motherboard: Asus Sabertooth Z97 Mark S CPU: Intel I7-4790K RAM: 32GB Primary Boot Drive: Crucial M550 256GB SSD Secondary Drives (ZFS mirror, non-boot): Crucial M550 256GB SSD and Samsung 830 SSD. sudo apt -f install ... 2 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Setting up grub-efi-amd64-signed (1.93.5+2.02-2ubuntu8.4) ... Installing for x86_64-efi platform. Could not prepare Boot variable: No space left on device grub-install: error: efibootmgr failed to register the boot entry: Input/output error. dpkg: error processing package grub-efi-amd64-signed (--configure): installed grub-efi-amd64-signed package post-installation script subprocess returned error exit status 1 dpkg: dependency problems prevent configuration of shim-signed: shim-signed depends on grub-efi-amd64-signed; however: Package grub-efi-amd64-signed is not configured yet. dpkg: error processing package shim-signed (--configure): dependency problems - leaving unconfigured No apport report written because the error message indicates its a followup error from a previous failure. Errors were encountered while processing: grub-efi-amd64-signed shim-signed E: Sub-process /usr/bin/dpkg returned an error code (1) Below is the output requested from cyphermox: sudo efibootmgr -v BootCurrent: 0000 Timeout: 1 seconds No BootOrder is set; firmware will attempt recovery Boot0003* Hard Drive BBS(HD,,0x0)..GO..NO........O.C.r.u.c.i.a.l._.C.T.2.5.6.M.5.5.0.S.S.D.1.................>..Gd-.;.A..MQ..L. . . . . . . . .4.1.4.2.C.0.0.5.7.B.4.D........BO..NO........O.C.r.u.c.i.a.l._.C.T.2.5.6.M.5.5.0.S.S.D.1.................>..Gd-.;.A..MQ..L. . . . . . . . .4.1.0.2.C.0.1.2.7.B.6.2........BO..NO........O.S.A.M.S.U.N.G. .S.S.D. .8.3.0. .S.e.r.i.e.s.................>..Gd-.;.A..MQ..L.1.S.H.0.E.N.C.A.0.9.3.1.5.6. . . . . . ........BO..NO........O.S.T.2.0.0.0.D.L.0.0.3.-.9.V.T.1.6.6.................>..Gd-.;.A..MQ..L. . . . . . . . . . . . .Y.5.5.D.T.Q.3.X........BO Boot0084* UEFI OS HD(1,GPT,67596964-080e-41ce-8b5c-42ce19e22bb6,0x800,0x100000)/File(\EFI\BOOT\BOOTX64.EFI)..BO Boot0085* CD/DVD Drive BBS(CDROM,,0x0)..GO..NO........O.T.S.S.T.c.o.r.p. .D.V.D.-.R.W. .S.H.-.2.1.6.D.B.................>..Gd-.;.A..MQ..L.9.R.J.6.8.6.D.D.0.8.8.1.L.5. . . . . . ........BO..NO........M.H.L.-.D.T.-.S.T.B.D.-.R.E. .B.E.1.4.N.U.4.0.................<..Gd-.;.A..MQ..L.P.R.O.L.I.F.I.C.M.P.0.0.0.0.0.0.1.6.B........BO sudo efibootmgr -v -c -L ubuntu -l \\EFI\\ubuntu\\shimx64.efi Could not prepare Boot variable: No such file or directory Unfortunately, I don't have a BIOS update handy as I'm already on the latest BIOS. I'd really like to reboot my system without down time. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1776271 Title: Could not prepare Boot variable: No space left on device (package shim-signed 1.34.9+13-0ubuntu2 [origin: Ubuntu] failed to install/upgrade: Unterprozess installed shim-signed package post- installation script gab den Fehler-Ausgangsstatus 1 zurück) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/shim-signed/+bug/1776271/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs