This is an issue to do with the default application of file types.
1. Set the default email application as Outlook.
Go to the Control Panel > Programs> Defualt Programs > Set your default Programs > Select Outlook > Select ” Set as Default Program”
2. Set Internet Explorer as the default application as your browser.
Set this in the same screen as above.
3. Set the following reg key – HKEY_CURRENT_USERSoftwareClasses.html. Verify that the Default value of this key is htmlfile.
Run > “regedit” > navigate to the location in the registry > Modify the registry value to “htmlfile”.
You could do this in an elevated CMD prompt as:
REG ADD HKEY_CURRENT_USERSoftwareClasses.htm /ve /d htmlfile /f