Error: top level design entity " " is undefined

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Hi...

Thanks for the reply....

There is no space character in the name.

Is there any specific location like 'bin' folder where the files has to be stored while simulating the program?

Please help me with this..

Thanks

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Hi,

you can check whether the file is in the project or not.

Project -> Add/Remove Files in Project

There you can see all the files which are used in the project.

If you don't see your top-level files use the "add" button to include the file.

Btw: Did you use the Project wizard for setting up your project ?