New answers tagged bcc
You could install a local mail client to manage the Gmail account instead of doing everything through the web-interface. For example, Thunderbird can be extended with the plugin Use BCC instead, which does exactly what you want. After installing it, you have to go to the settings and configure it the way you want (probably click on "send all mails as BCC")
If these mistakes are realised within 30 seconds of initiating a send, use of Google labs "Undo Send" might be of help. Find instructions to enable and customise it's settings below: Click Gmail's Settings Cog (top right above your main inbox listing). Note you may need to scroll down the page if you use, for example, the Gmail labs "Multiple Inboxes") ...
Sorry Julia, but it seems that functionality was not developed yet. The closest thing you have to stop that kind of auto-complete for new addresses is in Gmail settings: Click the cog at the right top corner and click Settings which will lead you to the Gerenal tab. Scroll down until you see Create contacts for auto-complete and choose the option I'll add ...
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