In Outlook, I received an email from GSSMO that says my local mailbox is full, what does this mean?

When you use G Suite Sync for Microsoft Outlook, your mail is stored both remotely in the cloud, and locally in a mailbox (PST) file on your computer hard drive. The cloud can hold up to 30 GB of mail (or more), which is a lot more than you'd typically want to keep locally on your computer. The amount of mail stored locally is instead limited by Microsoft Outlook's mailbox size.

If you receive this message letting you know that you have run out of space locally, older mail is removed from your computer and replaced with newer messages. But, all messages remain available in your Gmail account on the web

Most people can work normally with the default local limit of 1GB in Outlook.  This is the recommended setting for your local mail to ensure the best possible working experience in Outlook. The benefits for keeping the default setting at 1 GB would:

    To reduce the amount of data being stored on your computer hard drive
    To retain optimal sync time when using G Sync
    To maintain your overall computer performance and processing speeds

If it is necessary, this setting can be changed and the local storage limit can be changed.  To make this change;

    In the taskbar, right-click on the Google Apps Sync icon (1)

    Select Set mailbox size limit… (2)

    Select the 4GB radio button (3)
        WARNING: Do not choose Unlimited (slowest). This will cause performance problems.
        Click the OK button (4)

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