Gmail Server Error 707 is another common error that pops up when a user tries to send emails. A user will see an error message that looks like this: "Oops ... the system encountered a problem" or "There was a server error and your email was not sent". Disable the web browser add-ons if a user is using Mozilla Firefox or extensions in Google Chrome, then restart the browser.https://5e4296106616a.site123.me/blog/hoe-gmail-serverfout-707-te-repareren