Are you using Pop Peeper PRO (you may need to change an "AntiJunk" rule)?
What type of account are you using (Gmail, Yahoo, Outlook.com etc)?
From the Main Menu in POP Peeper --- if you go to "File" > "Error overview..." and then click on the "Copy" button in the interface you see and paste the copied information to this topic (right-click and select "Paste') we will then have more information that can help to identify your problem.
Absent additional information the following linked post may or may not apply to your issue:
Re: receive/view own email.
Keeping in mind that POP Peeper hides 'BCC' messages that you've sent to yourself, you have the option to view hidden messages by going to: "Messages" > "Hide hidden messages" from the POP Peeper Main Menu -- Note: hidden messages appear in italics.
Also, while awaiting further review of your issue by other members of the
Esumsoft Team, if you haven't already done so; you might access your account on-line to check your "Junk" folders to see if the BCC message may have inadvertently been sent there.
Good judgment comes from experience and a lot of that comes from bad judgment. - Will Rogers