@joseph_1979
I removed those cameras I could not see, and re-added. It worked.
Thanks !

At V8.12.1, the app said something about windows libraries. I followed the instruction and installed them.
But I still can't see some of my cameras. The Android version works, so there are something wrong with Windows app.
I can see: a Lumus, an Argus eco+sp, one of RLC-811As
I can't see: RLC-410W(two of them), one of RLC-811As

@tomselbyuk_331910860959874
It's same to me. I can't monitor some of my reolink cameras at this version. I can monitor on the android app. So this Windows app has defect.