The import was correct. Fixing build path errors is a common task after importing projects.
You'll have to look at the build path settings for this project and have to find out, which libraries are missing and dependencies are unresolved.
Right-click on the project name, --> Build Path --> Configure Build Path...
Check Projects and Libraries Tab, the reason for the red exclamation mark is in there.
You have to get rid of the build path errors, otherwise eclipse can't build the project. Either provide valid paths for all libraries or delete classpath entries.
The should remove that exclamation mark and eclipse can build the project. But removing classpath entries most likely results in compile errors or runtime errors, if the application can't find external configuration files or so.
In your special case: Looks like the project depends on other projects (we see that quite often in eclipse) and it could be, that your boss did not give you all projects or your eclipse is not setup correctly (maybe your workspace should contain some default projects with default libraries). Ask co-workers, they may give a hint on that.