Hi NadiaRavanello
I'm sure the MYOB Community would be happy to offer assistance with the In Tray. However, could you provide some more context into what is occurring- for example, are you selecting the In Tray button and it doesn't appear on screen? Are you getting an error message? Is it a case of you can open the window but you can't upload a document?...
If you are encountering the situation where you are selecting the In Tray button and nothing is appearing on screen, try selecting that option and going Windows (top of the screen)>>Cascade. What this will do is pull all the open windows onto the screen, so if you have accidentally moved or for some that window is appearing off-screen it will be pulled back so it can be accessed.