### 1. Open the APT `sources.list` File
```shell
sudo nano /etc/apt/sources.list
```

### 2. Remove any `cdrom` entries
* Sometimes Debian Adds the Install CD (aka. the Install USB) as a source for apt packages
* If `apt` can't access an entry it just throws errors
* Should the `sources.list` contain Lines starting with `deb cdrom:[Debian...` comment it out by adding a `# ` to the start of the Line

### 3. Update APT
After Saving the `sources.list` file Update apt by running
```shell
sudo apt update
```