k9 mail - All emails under K9 -app?

Android requires at least one-working Gmail that is apparently tied to the default email. Now I would like to have that email under K9 but I cannot because Android instructs me to hard-reset my device if I remove the Gmail from the default Gmail. Now the problem is that I get two notification from Default client and from K9. So how can I have all emails under K9?

Answer

You don't need to remove default Google Account or factory reset to ditch double notifications. Use any one of following methods which suits you best:

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  From Settings ~> Accounts & Sync, choose the default Google Account & turn off Gmail Sync. After that, you'll receive notifications from K-9 Mail, ONLY.

  
  


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  In some Android versions, if you turn off all sync options listed under a Google Account, a Sign Out button is appeared. All you need is to tap it. Go ahead to try it.

  
  
  


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  If you are rooted, delete /data/system/accounts.db file & restart the system (On Jelly Bean, its /data/system/users/0/accounts.db and the location can vary with Android versions). Next time, you'll be asked to add Google Account again.