Office 365 account requires repeated login attempts

If your Nine is trying to logon to server every x hours by server settings when using ADAL, please contact your server administrator to change the Token Lifetimes Settings with the following link.

Token Lifetimes

https://azure.microsoft.com/en-us/documentation/articles/active-directory-b2c-reference-tokens/

In addition, if it is unable to be changed, please remove your account and then set it up again from the scratch. When setting up your account, please use 'Exchange Server or Others' option rather than 'Office 365' option.