Using Classic Outlook on Windows for personal email, calendar, and contact management
Hi @gary s
I understand how frustrating it must be to receive hundreds of junk emails while Outlook will not save changes to your Blocked Senders list.
This issue can occur when the combined Blocked Senders, Safe Senders, and Safe Recipients lists have become too large. In Classic Outlook, please select Home > Junk > Junk E-mail Options, remove any outdated entries from these lists, and then try saving the changes again.
If you are using an Outlook.com or Hotmail account, you can also sign in to Outlook on the web and manage the list under Settings > Mail > Junk email. If the same error occurs there, the issue is likely related to the mailbox rather than the Classic Outlook application.
Since spam senders often use constantly changing addresses, blocking each sender individually may not be effective. I recommend selecting the messages and using Report > Report Junk so they can also be submitted to Microsoft’s filtering system.
I hope this helps. Please feel free to let me know whether you can save the settings after trying these steps.
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