You can also run Apple Mail’s Connection Doctor to find more information about login failures or network issues. If Gmail is experiencing a temporary outage, check Gmail for a status message.If the Mail app is rejecting your password, check your Gmail account password settings.If the status says Login Failed, check that your Gmail account is set up correctly on your Mac Mail app.If the status says Network is Offline, check your Internet connection then try opening Mail app again.If there is a status icon, click on it and perform one or more of the steps below, depending on what the icon information tells you. When you open your Mac mail, look for a status icon such as a lightning bolt or warning symbol beside your Gmail inbox on the Mail sidebar. Apple recommends these next steps when you can’t send or receive email on your Mac, so it’s worth trying out. With the two basic steps into solving the Gmail not showing emails in Mac mail issue out of the way, let’s look at more advanced troubleshooting steps. If the messages are all there, then the problem is with your Mac Mail app and not with your Gmail account. You can also try accessing the Mail app on your iPhone, and check if all of your Gmail messages are showing up. Try accessing your Mail app on your iPhone.If you’re not yet running macOS Ventura, you’ll find this in System Preferences instead. To install macOS updates, simply go to System Settings > General > Software Update. I can’t emphasize enough the importance of keeping your Mac’s software up-to-date. If you haven’t embraced the habit of updating your Mac’s operating system whenever Apple pushes new versions, now is a good time to start. More often than not, rebooting your Mac solves hardware and software-related issues such as Gmail not showing all emails in Mac Mail. The first thing you need to do is, of course, restart your computer.

There are several steps that you can take to fix issues with Gmail messages not showing up in your Mac Mail app.

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