(I posted this to an old thread but now realize it should be posted as new):
I cannot screen mirror my Android phone to my Roku Express+. Both phone and Roku show a connection but the Roku mirroring progress screen just freezes and times out. There is no mirroring. There are numerous similar posts from others but no solution! Screen mirroring is advertised as a feature of the Roku Express+. So Roku needs to respond with a solution. Details:
My Roku Express+ 3910 is connected to a TV with the HDMI cable. My LG (Android 7) phone's screen mirroring screen (Wifi Direct under Advanced Wifi) says it found and is connected to the Roku Express+ 3910. I have gone to Wifi Networks on my phone where the Roku connection is listed, and entered the network connection password.
But when I connect my phone, my TV's Roku screen stays frozen on the "starting video from ... [my phone name]" screen with progress on the progress bar stuck about 1/5 of the way. Stop Video and Options are also displayed on the frozen screen. The Roku either stays frozen on this screen or after a long wait times out and returns to the Roku home screen. Or I can press the home button to return to the Roku home screen. If I check the Roku Systems menu, Screen Mirroring > Screen Mirroring Devices, it shows my phone listed (always allowed).
Like the others on this thread the connection request is accepted and the Roku screen changes to Receiving Video from “laptop” with a progress bar of 30% that does not change. Within 5-10 sec the connection is dropped. DxDiag shows laptop Miracast capable of HDLC(sp?).
My laptop DXDIAG reports "Miracast: Available, with HDCP". When I open the right panel and select Project, the tell it to "Connect to a wireless display", I see all three Samsung TVs on my network, two Roku Ultra players, and two Roku TVs. My laptop is connected via wireless, one Ultra is wired, and the rest are a mix of wired and wireless connections. My biggest problem is that I have two Ultra players on my network, and there's no way to tell the difference. So I click them both and wait for the one I'm using to indicate it's connecting. At this moment I have my laptop screen duplicated on my TV via the Roku. I can also change it to Extend, and it's like I have two monitors connected to the laptop. It only takes about 5 seconds for the screens to sync, and I'm not seeing any lag between the laptop screen and the projected screen.
So, Windows 10 version 1909 is screen mirroring without an issue to my Roku. This includes the video and audio. If I change to extend instead of duplicate, I was hoping to see the resolution on the TV go to 4K, but apparently my laptop display adapter doesn't support 4K, at least over the Project function.
Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution." If you appreciate my answer, maybe give me a Kudo.