Workbench problem in android

I copy my workbench all project folders except two project from another location D: drive, but there was created a problem, when I ran the Eclipse.Then I did the same job reverse,but it is necessary to set-- window->> preferences->> location of path of android SDK, why?. And I have not restore my previous all project in to eclipse project explore section.

Now, when I run eclipse the after the import new archive file, then I have faced just like picture red sign occurs my eclipse.

NOTE: I have copy .metadata folder as we开发者_Python百科ll.

My Problem

It is necessary again add google mobile add to my project?

Based on the answer, I suppose that you have to check your build path and set the proper location for your libs.

do you have import the projects to your workspace or just copied them? if you've just copied them try to clear the workspace (do NOT delete your projects on your drive, just remove it from the workbench) and import the projects again (right click in package explorer -> import -> general -> existing projects into workspace).

it's difficult to say what is wrong without any error logs.