Third-party add-ins are helpful… until they’re not. Outdated or conflicting ones can mess with Outlook’s core performance, causing unexpected slowdowns or outright failure to launch. Create your account and connect with a world of communities.

Follow the on-screen instructions to update your Office apps. Then, launch your Outlook app, and it should open without problems. If your PC has a virus or malware infection, that may be why Outlook isn’t launching. In this case, run a full virus check on your PC to find and remove any threats.

In some specific cases, we observed that the problem no longer stayed after deleting the Outlook App Data folder. Thus, you can try deleting the Outlook App Data folder and check whether Outlook functions in your case