2013 Home and Office Outlook - Pop email incoming email disappear

Question

I have Microsoft Office Home and Business 2013 (current updates) using the same email POP account for over three years. 
For weeks, I’ve seen incoming email disappear.  My Desktop Alert shows new email incoming then it disappears from the inbox.
I know these emails were sent to me because my co-workers have emails that show me cc’ed that I did not receive.  
Where are these disappearing emails going or are they being rejected?
I was forced to perform the 8.1 upgrade, no impact on Outlook
I checked and have all Office updates current
I’ve checked my other device’s email apps and those emails were not located there.
I’ve checked my Outlook Options: Conversation clean up:  added
/checked – Do not move unread messages
I have Disabled all:
Add-ins,
Rules and Alerts, no folders
No security add-ins
Not sure on - View and manage Microsoft Office Add-ins  

Answer 1

This may be caused by different reasons, but the most likely reason is on the custom setting. To help you investigate what happened to your messages, we'll walk you through a step-by-step process to eliminate possible causes of your missing messages:
Step1: Check web server - Please check your web serve to see if those missing messages are out there.
Step2: Search all messages - Try to search the messages that are missing. Remember to click
All Mailboxes button before searching.
Step3: Check junk mail setting - They are probably set to delete mail rather than send it to the
Junk E-Mail folder.
Step4: View filter - Please check your View filter
to see if you have set any filter rules to the incoming mails.
Step5: Forwarding settings - Please check in Account settings dialog to see if you have changed the default deliver location of your account.
Please follow above steps to see if you can find your missing data.