When I first installed KEIL5 on my computer, I didn’t encounter any issues. However, a few days ago, my C drive got corrupted, and after reinstalling the system, I faced problems while installing KEIL5 again.
After the normal installation of KEIL5, I started the PACK installation, but it kept failing. At that time, I was using a wireless network, and I couldn’t access the website http://www.keil.com/dd2/Pack/. I wasn’t sure if it was a problem with my computer or the wireless network. Later, I switched to a wired connection, and the PACK downloaded successfully. However, when I reached the last step of the installation, it reported an error, and the PACK installation window became unresponsive and greyed out. I had to use CTRL+ALT+DEL to force it to close. This happened repeatedly for several hours, so I decided to give up.
I downloaded the required DFP files for the chips from http://www.keil.com/dd2/Pack/, like these two:
I saved them to a location, then double-clicked to install. After the installation finished, the KEIL5 software prompted me, and I just clicked confirm, and it was all set. 