Replicated on both Windows 8 on a surface pro and windows 7.
I am an office 365 E3 customer. Recently I have been presented with endless popups to validate my office account when using office 365 (office 2013) apps (outlook, onenote, word etc.). I am using the trial version, eagerly awaiting the opportunity to use office 365 as part of my E3 subscription entitlement.
The popup indicates that I need to validate my account. It works and I can log on any time to Office 365. The message reads "Call us overprotective, but we need to verify your account again before opening this document." I enter my office 365 ID and I am then promoted to confirm if the account is personal or business. I've tried both, many times (>50 in the last 3 days on 2 workstations) and neither appears to address the issue. After entering my password (confirmed) the popup disappears. It returns within 15 min give or take, and in a number of Office apps as noted above.
One possible issue is that my live ID and my Office 365 ID are the same email address (I moved my email to Office 365 and really had no choice but to continue to use it. I raise this as the popup asking me if the account was personal or organizational seemed odd.