Junk emails with mulitple domains

Preventing false categorization of messages as junk is why you review the Junk Email folder periodically to find those messages that should have been delivered to Inbox. The limit for the Outlook.com Safe Sender list is 1,024. You can't have more entries than that. While I agree you should have more control, Outlook.com doesn't provide it. Reporting junk on CleanTalk.org for messages received in an Outlook.com mailbox won't help, from what I have read of their documentation.

Free email services may not be able to properly filter the latest spam messages.
Please try developing a new application using macros in the classic Outlook (desktop version), not the browser-based version.
By analyzing the Internet headers of received emails, you can filter them by sender, IP address, wildcards, and other criteria, and then move them to the Junk Email folder.

<Japanese>
無料のメールサービスでは最新の迷惑メールを分別出来ない場合があります。 ブラウザ版ではなく、従来のOUtlookにてマクロで新規アプリケーションを開発してみてください。 受信したメールのインターネットヘッダーを解析すれば、差出人/IPアドレス/ワイルドカードなどで分別出来ますので迷惑メールフォルダに移動させてください。

Hi. I'm Brian and I'll try to help.

Do these messages arrive in your Inbox or your Junk Email folder? If the latter, that's how Outlook.com works. There is no option to completely prevent the delivery of messages. You can only control which folder receives them. Any address or domain you add to the Blocked Sender list will cause messages from that address or domain to be delivered to Junk Email. It won't stop the delivery.

If they're being delivered to your Inbox, one approach you can take is to log into https://outlook.live.com/mail/options/mail/junkEmail and select the button marked "Strict" in the "Incoming email handling" section right at the top. This will cause all messages you receive to be placed in the Junk Email folder except for those messages from an address or domain in your Safe Senders list or your Contacts. Those will be placed in your Inbox. Periodically, you can review the list of messages in the Junk Email folder by viewing the From addresses and subjects and marking those as "Not junk," after which you can simply empty the folder or wait for 10 days until Outlook.com automatically deleted them.