How does Google's SMTP service handle user credentials and privacy?

The potential risks of sharing spreadsheets containing sensitive information like email credentials include unauthorized access, data theft, and potential misuse of the information. Solutions could include encrypting the spreadsheet, limiting access to only necessary individuals, and regularly updating and changing passwords. It's also advisable not to share such sensitive information through spreadsheets if possible.

Some alternative methods to SMTP for sending bulk emails include using API-based email delivery services, such as SendGrid, Mailgun, or Amazon SES. These services provide a more robust infrastructure for email delivery and often include features like analytics, bounce handling, and spam prevention. Another alternative is to use a marketing automation platform like Mailchimp or HubSpot, which provide tools for creating, sending, and tracking email campaigns. Finally, you could also consider using a dedicated bulk email software, which can handle large volumes of email and provide features like list management, templates, and reporting.