Recently, any PDF that I open in Adobe Reader causes the image of the pdf to display, but then after a few seconds it goes grey and a white rectangle appears over it. Must use Task Manager to kill Reader. To fix this, following a suggestion on the community forum, I selected 'Disable New Acrobat' in the settings.

Using Windows 10. The Reader version number currently says 2023.008.20470. I don't know if it was the same as this before I did the disable.

Unchecking 'Enable Enhanced Security' had not fixed the problem. Protected View was off. I also tested it with my antivirus program shut down, to no effect.

I see in the community forum many posts over the last few years that talk of freezing like this, with various solutions proposed. But this one only started occurring in the last few days or weeks, presumably after a recent update. I don't know what 'disable new acrobat' means, but at least I can view my PDFs now. I thought you should know about this bug!