What is Error Code 77375 in Gmail?
This error indicates that you are sign in to Gmail account from multiple devices. One of the devices is not secure because you might be accessing the email account in different locations.
How to Fix Gmail Error 77375 Code
First of all log out from all devices. This is the very first thing you have to do. Now change your Gmail password. Once done, you can log in to your target platform, for example, Google Workspace, Outlook or any desktop email client.
*Don’t use your Gmail account on multiple devices with different locations.