Error 300 can occur at sign in or when using the Outlook add-in. Check the steps below to see if these resolve your issue.
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If attempting to sign in with your email address and password, clear your cache and cookies, then try again.
If signing in with Google, you may need to re-sync your Google and Zoom accounts. Go to Zoom's Sign Up and click Sign Up with Google to re-sync your accounts.
If you are still receiving error code 300, submit a request to Zoom Support for troubleshooting assistance. Please provide the following: