I have created a exe in windows application

You didn't mention 'client is unable to run it' in detail. I am certain there must be some error somewhere shown. Just 'unable to run' doesn't help much.

 

Have you ensured that the client machine has required version of .NET installed already?

 

Have you put some exception handling in your code and have written exceptions to text file?

 

Are other dependencies such as database etc deployed too? Are there any permissions issues?

 

You will need to investigate from all these directions.