cannot set up gmail - says cannot connect to imap server. ??
Are you able to load your Gmail account in Safari?
This Google article might help you out -> Setting up Google Sync with your iOS device
If you don't want to use Google Sync (If you're not sure, I'd recommend using Sync), you may want to check this doc out -> Gmail iOS App
Try backing up, doing a reset, and re-putting everything back on, or try reseting the entire "Mail" app in settings
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