Ok, can you open your services console and scroll down to S for SQL Server. You should now see the services. Please ensure SQL Server (SQLEXPRESS) is running and then try .\SQLEXPRESS instead of (local).
So as per your example:
Server type: Database Engine
Server name: .\SQLEXPRESS
Authentication: Windows Authentication
Hope this helps
Update: These instructions are because I assume you are running Express Edition not Dev/Std/Ent edition of SQL Server
Try ensuring the appropriate protocols are enabled:
- Start the SQL Configuration Manager (ie: Start->Programs->SQL Server->Configuration Tools)
- Expand the SQL native Client configuration
- Click Client Protocols (you may have a 32-bit and a 64-bit, apply to both)
- Ensure Shared memory, TCP/IP, Named Pipes are enabled in that order
- Expand SQL Server Network Configuration
- Ensure Shared Memory for either SQLEXPRESS and/or MSSQLSERVER is enabled
- Click SQL Server Services
- Restart any running services
You should now be able to login to the instance
If you find you cannot login at all you may need to follow these instructions to get SQL Server into single user mode. See here for the full instructions from Microsoft.
By default, sqlservr.exe is located at C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Binn.
If a second instance of SQL Server is installed, a second copy of sqlservr.exe is located in a directory such as
C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\binn.
You can start one instance of SQL Server by using sqlservr.exe from a different instance, but SQL Server will start the version of the incorrect instance as well, including service packs, which may lead to unexpected results.
To avoid this, use the MS-DOS change directory (cd) command to move to the correct directory before starting sqlservr.exe, as shown in the following example.
cd \Program Files\Microsoft SQL Server\MSSQL10_50.1\MSSQL\Binn
To start the default instance of SQL Server in single-user mode from a command prompt
From a command prompt, enter the following command:
sqlservr.exe -m
Single-user mode can be useful for performing emergency maintenance when you do not want other users to connect to SQL Server, but any user can become the single user, including the SQL Server Agent service.
You should now be able to login to the instance and add yourself to the security tab and grant full access.
Alternate Method:
THere is a script here that claims to add the current user to the SQL Server sysadmin role. This may work in single user mode but I have not verified it
I would first verify 100% which instances are installed and what they are named. Go in to Services and verify what they are called ie. "SQL Server (SQLEXPRESS)" or "SQL Server (MSSQLSERVER)". Ensure the services are started.
Then like @BryanS. said ensure the SQL Browser service is running.
Lastly as you are running on Windows 7 you must ensure ensure that you install SQL Server 2008 SP1.
Best Answer
If you've done a standard install using the default name (i.e. not a specified instance name) you should be able to connect to either "localhost" or "DM".
Does SQL Browser not return the name of the local service when you browse for SQL Servers?