After El Capitan upgrade Mail stuck on validating

[cosrocket]

I just did an El Capitan 10.1.1 upgrade. When I clicked on the Mail app it said Mail was upgrading, and now it is stuck on validating accounts and Mail will not open.

How can I get my Email to open? I'd appreciate your help with this.

 

[Queen6]

Try reboot the system and start up in safe mode, this can sometimes help to clear out the caches. 10.11.0 destroyed my email, had to remove all accounts and set up everything again from scratch, amongst multiple issues mostly related to Apples own software. Whoever "green lighted" this release needs a good "slap" for stupidity alone...

Q-6

 

[Eduardot]

I came back to Yosemite, luckily i had a time machine backup. Will wait until they quirk out all those nuisances.