The Gmail Problem is quite common among Gmail users. All of the Gmail users have faced this issue at least once. Like that one most common issue which is faced by the users is In this issue an error message "oops... a server error occurred and your email was not sent. (#007)" comes on the screen again and again. Various methods like history and cookies cleaning, chrome cleaner kits, registry checkups, and repairs checking extensions are not works for that situation. one of the most popular methods is Disable Email Signature from Avast. Follow the steps to solve this issue:-
In AVG, you can find this setting listed under Settings > General. Once you’re there, deactivate the checkbox associated with Email Signature and hit Save.
In Avast, go to Settings > General and disable the checkbox next to Enable Avast email signature and hit Save.