Hi @Peter Le Breuilly ,
Welcome to our forum!
Looks like your issue is related to your Hotmail account, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. Based on my research, i found a similar thread as yours, which mentioned the useful solution:
It's suggested that you could try it to check if there're any differences. If it doesn't help, it's suggested that you could post your case in dedicated forum for Outlook.com for more professional advice.
Thanks for your understanding and support!
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