Syncing Outlook Calendar with Yahoo

[Larry J]

Asking for assistance syncing my Outlook calendar with Yahoo calendar. My office email is yahoo-based, but my email address is "myname@mycompany.com. I had no problem creating an email account in Outlook thereby importing all Yahoo email. I can send/receive email from work desktop and personal iPhone. No problems. I can't figure out how to sync the Outlook calendar with Yahoo. When I accept a meeting invitation at work, I'd like it to appear on my iPhone. The iPhone is synced with yahoo calendar, but not Outlook. Can this be done without using third-party app or software. Thanks.