
The purpose of the inbox is to filter spam and other unwanted messages. However, some users, have discovered their “filtered” inbox full of legitimate messages that never made it to the main inbox or to the Messenger App.
When using the Messenger App, the hidden inbox is buried under four menus. To get to it tap Settings, then People, then Message Requests and tap on the “See filtered requests” link.
The filtered messages include anything sent to you that you have manually filtered out as unwanted, as well as messages from people who are not connected with you on Facebook.
Some have reported finding messages informing them of a friends death to those who have won contests.
See the detailed instructions on how to get to your hidden inbox below.
Check your hidden inbox and let us know below if there are messages you wish you had received.
Source: CNET