Why Delphi says 'cannot resolve unit name xxx'?

Question

I\'m working with Delphi2010 Enterprise Update 4.
When I\'m opening my project in the IDE and displaying the mainform code, there are 2 unit names underline in r

Answer 1

Closing and reopening a project usually helps to get rid of most of these errors. Try it...

_{(That doesn't change the fact that nowadays, this is probably my number one annoyance in the IDE...)}