[WSL] Solution for the phenomenon that 404 is displayed when trying to insert Java with apt (personal memo)

environment

Windows10 Education 2004 WSL Ubuntu18.04 LTS

phenomenon

I ran the following command to install Java on Ubuntu 18.04 on WSL ...

sudo apt install default-jdk

The installation fails with a 404 error like this.

Ign:1 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 libnss3 amd64 2:3.35-2ubuntu2.11
Err:1 http://security.ubuntu.com/ubuntu bionic-updates/main amd64 libnss3 amd64 2:3.35-2ubuntu2.11
  404  Not Found [IP: 91.189.88.152 80]
E: Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/n/nss/libnss3_3.35-2ubuntu2.11_amd64.deb  404  Not Found [IP: 91.189.88.152 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

apt-get update and apt-get --fix-It says to try missing, so I tried it, but it didn't improve....

 There was an article saying that it was caused by anti-virus software, but it doesn't seem to be relevant because I haven't introduced anything like that.

# Solution
 When I ran the following command, the error disappeared.

sudo apt-get autoclean //This is liver-like sudo apt-get update

 Apparently there are still old files that aren't used, and it's not bad ...
```sudo apt-get autoclean```Seems to be a command to delete such unnecessary files.

# reference
https://qiita.com/kabosu3d/items/0f436ba05df8ac358245
https://qiita.com/Y_Aowashi/items/d355d90945305d925a3c