after 3.4 upgrade can't add any plugins

Yesterday I upgraded to 3.4. I woke up this morning to find spam out the wazzoo, so I check my admin dashboard. No plugins. I then tried to install plugins. Yet the installation fails every time.

I am very thankful for WordPress. However, I am disappointed that this upgrade has become more time consuming than usual. Perhaps if someone had created an installation document for us. Then we could have read it and decided when we wanted to upgrade our sites, because now I’m in a pickle. I have a business to run and don’t time for another day of fooling with this.