Type Into using SendWindowsMessages types nothing

I have a process that opens Access and clicks Browse to choose the file to open.
Then I have a Type Into activity that enters the file path of the file I want to open.
This worked well. But I wanted to run this process in the background, so I checked the SendWindowsMessages box. And now it doesn’t type anything, but does not give an error. I tried it with SimulateType, but it also didn’t work. Robot is only able to type the file path using the default method.
Any ideas how I can fix this?


I tried using Type Into activity to type something into notepad.
This worked with all three methods: default, SendWindowsMessages, and SimulateType.
But when I try to type something into the window below, only default method works.