Blender 2.91 Addons Not Loading

I’m running Blender 2.91 under Windows 10 Pro on AMD Ryzen 9 hardware with 32GB RAM and an nVidia GeForce RTX 2080 Ti graphics card. When I try to install an addon via the usual process, it takes about a minute before I can tick the ACTIVATE box. Some addons refuse to install at all and give no indication of what is wrong. Anyone know what causes these annoyances and a fix? I’m a retire IT support tech and always keep drivers up-to-date.

@ kurasdan: While I am sorry that I don’t have a solution for you on your issue, I do have a question?

Are you having any issues with the rendered view in Cycles? Any issues with perhaps Cycles using the Render denoising sample settting for the viewport Denoising sample settings? Any issues with every new Pricipled BSDF material created having emission strength set to one? I’ve been having issues with a number of things in 2.91 so far.

My problem does not concern rendering. It concerns problems I’ve run into installing addons.