You need to make outlook default application for sending emails. Please follow these steps:
Step 1: On the Outlook menu, click Options.
Step 2: Under Outlook Options click General
Step 3: click Make Outlook the default program for E-mails, contacts, and Calendar.
In what mail client did you configure your live.co.uk (hotmail) account? If you configure the account in a different mail client, please try set Outlook as the default mail client and then test the issue again. To do this, go to Control Panel\All Control Panel Items\Default Programs\Set Default Programs, select Outlook and then click "Set this program as default".
If you mean you configured the live.co.uk (hotmail) account in Outlook, and when clicking an email address hyperlink, it defaults to create an email from the Hotmail account, please try set your business account as the default in current profile and then test the issue again. To do this, go to File > Account Settings > Account Settings, highlight your business account and click Set as Default button.
If I've misunderstood something, please provide more details to clarify the problem.
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