Unable to open physical file, operating system error

Some time,when you try to attach database file (.mdf, . ldf) to sql server , you might get the error

"Unable to open physical file, operating system error" 

The reason behind this is that the account from which you are accessing the file , does not have rights for this specific folder or file.

Solution for this is that , you have to give the rights. In my case i have given the rights to the local administrator

After giving the rights , try to attach the file again.

I have attached the database successfully.