Fix Microsoft Outlook Error Either There Is No Default Mail Client Or Not Fulfill Messaging Request

Steps to fix Microsoft Outlook Error Either There Is No Default Mail Client Or The Current Mail Client Cannot Fulfill the Messaging Request. Please Run Microsoft Outlook And Set It as the Default Mail Client

Step 1) Make Outlook a default app
Step 2) Repair Office
Note- Online Repair may reinstall office
Step 3) Disable Cortana
ComputerHKEY_LOCAL_MACHINESOFTWAREPoliciesMicrosoftWindowsWindows Search
Name the value “AllowCortana”. Double-click it and set the value to “0”.
In future if you want to enable Cortana set the value as 1

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how to repair outlook 2016