I hev installed it because i need it for a private server ,but when i am trying to connect to server it give me this error can you help me?

did you install the Database Engine when you installed SQL Server 2008 R2?

i checked all the files when i choose

maybe my server name is wrong?

I hope you must have used. ServerNAme: PC-NAME\SQLEXPRESS

yes,it connect but now says login failed for user "as" where do i make user and passs?

You can login using Windows Authentication and then go to Security->Logins to create user.

if i use sql server authentication ,how do i do that/

Send me detail error.Have you ever created User "as"

yes,and when i installed sql i enter at security mixed ,and inserted a password

i mean no,where do i have to create it?

But you said you have inserted password correct? Use User "sa" and then put your password.

thanks for all you help