Have you checked the logs for what the error is saying?  Also what account are you using to install it?  Does that account have access to SQL since you are using Windows Authentication.

Thanks for your reply i don't have admin access to sql server that's why iam getting that error now it's rectified thanks for your clarification.

another issue i got can you please help on these i am getting error while activating feature of nintex 2013 in site collection features

What is the error that you are seeing?

The content type with Id 0x0108010064E42B14ADA442C78E98D686760A8493 defined in feature {86c83d16-605d-41b4-bfdd-c75947899ac7} was found in the current site collection or in a subsite.

This is the error eric

I've seen that before and honestly didn't troubleshoot it as best as I can.  From what I know, I had a conflict between moving list from one site to another that had Nintex deployed to it previously.  Are you moving a list from one site or farm to another?

Did your initial SQL issue get resolved?  If so it might be good to start another discussion around the error you are seeing.