Hello! I believe I have found a bug when trying to view videos through irfanview. This seems to be related to NVidia's graphics drivers, as I just updated on Feb 1, 2019 when I first noticed this issue. Upon opening the video with DirectShow enabled, I see a black video player while the audio plays normally. Then I open the same video a second time, so that a second irfanview window opens, and that same video plays fully in the second window. This appears to happen for both 32 and 64 bit viewers, and both while running in normal and administrator mode.

I've take a screenshot of the two players next to each other:

The sample webm that I am testing with came from here: http://techslides.com/sample-webm-og...iles-for-html5

OS: windows 10 pro
GPU: Nvidia Geforce 980ti
Geforce Drivers: 417.71
Codecs: K-Lite Full pack, installed on Feb 3, 2019

-In Event viewer, no warnings or errors seem to be logged at all.
-When you finally do have the second video playing, if you close the first window and open any other video files, they will show the same symptoms.
-This appears to happen for any video files. I have tested with mp4 and webm.