Do you need both .net 3.5 and 4.0 installed or just .net 4?

Question

to run both 3.5 and 4.0 web apps?

Answer 1

I found that I needed 3.5 even though I have 4 installed. Without 3.5 I was getting GfxUI has stopped working error. Despite installing the latest Intel Drivers for G41 chipset The error would persist. I then found a post which said it requires .net3.5 and as soon as I installed this I was OK. So... as previously said it all depends on the apps you have installed. If they need 3.5 then you need to install both.