Updated Plugins and Now Website is Not Working Properly

We updated WPMU, CoursePro and MarketPress plugins and now website is not working properly and is in disarray.

The store content is no longer available and it gives us an error that product pages are not available. It also deleted website header.

Can you please let us know if there’s a quick fix we can perform on the website?! We read through your community blog that NEW versions have bugs and users are having problems updating plugins. Has this issue been rectified? What would be the step we need to take to get the site back up and running if BUGS have not been fixed?

Your quick attention to this issue is appreciated.