I want to install some applications but for any installation command it says that this package has no installation candidate. I can't even run sudo apt-get update.
cookie98@cookie98**:~$ sudo apt-get install software-properties-common
[sudo] password for cookie98:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package software-properties-common is not available, but is
referred to by another package.
This may mean that the package is missing, has been obsoleted, or is
only available from another source
E: Package 'software-properties-common' has no installation candidate
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