E: Could not get lock /var/lib/apt/lists/lock. It is held by process 984 (packagekitd) N: Be aware that removing the lock file is not a solution and may break your system. E: Unable to lock directory /var/lib/apt/lists/ code example

Example 1: E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable) E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?

ps aux | grep -i apt

sudo kill 
# Check if the process was killed by running the ‘ps aux | grep -i apt’ command. If it is still running, force kill it with SIGKILL signal:

sudo kill -9 
# Another, easier way would be to use the killall command. This will kill all the instances of a running program:

sudo killall apt apt-get

Example 2: E: Could not get lock /var/cache/apt/archives/lock - open (11: Resource temporarily unavailable) E: Unable to lock the download directory

sudo killall apt-get