Running Outlook 14.5.9 (latest 2011 version) on El Capitan 10.11.2. 

When I click the Receive Mail button, most of my 10 or so pop3 email accounts are checked for waiting mail. A few are not. However if I select one of these accounts directly in the Send/Receive account list, any waiting email is downloaded. 

It seems to me that long ago (possibly back in Entourage days) there was a check box for whether to include a particular account in Receive All. As far as I can tell that option has been eliminated. These few accounts seem to be acting as if the option existed and was not checked. 

It's not a problem with user ID or password, obviously, since the accounts work fine when selected directly. 

They all seem to be gmail accounts, either created directly at gmail or else created through an organization (for example IEEE) that uses gmail as its email provider. But other gmail accounts (some of each kind) work fine. 

I wondered at first if it was related to whether these accounts were also on my iPhone. But in fact I have two gmail accounts from organizations on my iPhone. One works and one does not, in Receive All on the Mac. 

The affected accounts are all POP3, not IMAP.